SPRING and fall in mountain counties of northeastern Washington, frontier gatherings revive in the form of Okanogan, Stevens, and Ferry County Barter Faires.By the time my friend Debbie, her two sons, and I drove down into the vast upland valley where flowered an October Okanogan Barter Faire on Tunk Mountain, we had driven less than 100 miles from our homes on Sanpoil River ... but the road might have taken us 100 years into the past. At the entry booth stood a flatbed truck carrying a veteran cider mill, double-ended "country music" drums, a white Saanen goat in one slatted pen, and a Brobdingnagian red rooster in another. Behind us, along the dusty mountainside road, a once-blue school bus towed a motor home half its age. All manner of vehicles, from VW bugs to caravans with outdoor sitting rooms on their roofs, thronged the valley in covered-wagonlike circles. Stalwart white-gleaming tepees stood beyond them, this side of an outermost ring of pine trees rising above this gypsy encampment. Just as frontier trappers used to gather to sell and swap furs at Rendezvous, so the mountain dwellers of northeastern Washington have, for the last 19 years, congregated each spring and autumn at these long-weekend barter faires. They come to exchange handmade goods, inherited bric-a-brac, livestock, garden produce, canned salsa and fresh oysters from Puget Sound country, truckloads of mirrors, and home-cooked bakery goods. But there's also some important trading of religious beliefs and sometimes guarded marketing of war stories, from Vietnam, Korea, and World War II. For many men, Barter Faire is as much a spiritual venture as a commercial one. As with those old mountain-man get-togethers, the schedule for Barter Faire isn't set until it's proper to be set and doesn't happen until it happens. But unlike the gatherings at Rendezvous, where ribald feasting and drinking transpired, no liquor is allowed. A young man with a walkie-talkie directed us to a spot where we could spread a multicolored blanket and set up the two leather Texas saddles with brass fittings (built before plastic was born) that I'd brought. Debbie had a .22-caliber pistol she wanted me to sell (a sign described it; the pistol was in a box), plus her "attention getter," a silver tureen upholding 300-some peacock feathers, each 3 to 4 feet long. "I want 50 cents for the smaller plumes, 75 cents for those with an 'eye' inside the circle at their end," she told me, adding, "I don't really care if I sell them or not. I'm kind of attached to them." With that, she loaded her three-month-old son, Justus, into a backpack, left her three-year-old, Paige, to play with other children nearby, and went in search of a mountain woman named Opal who had promised payment on a previous Barter Faire's purchase. Along came a man named Tebor riding a tall, sinewy, beautifully marked appaloosa. I learned that Tebor had, during the 1956 Hungarian revolution, been brought by his parents to North America. "Today, two friends and I just rode over 30 miles from beyond Tonasket. Five hours," he said proudly, patting his steed's neck. Of the appaloosa, he explained: "I got him here three years ago when he was six months old. Traded three hides for this colt." And he smiled like an inland pirate. Indeed, it was a tale out of "The Arabian Nights." Near my blanket "store," a three-piece band (flute, guitar, and a double-ended drum hung around a young man's neck) played from the flatbed of a truck. Six girls - some in buckskins and long skirts - began dancing patterns on the meadow whose grass had grown long again since the last gathering. Women passed by carrying infants papoose-like or dragging them from the ends of their long skirts. These were children who answer to names like Spring Rain or Shooting Star. A BROWN-BEARDED man wearing a wide-brimmed felt hat and a multicolored serape similar to those I'd seen in Buenos Aires, walked up with his wife to ask the price of my saddles. "$350." He smiled. "We're pricing them. Come spring, we're moving out here to 40 acres." He pointed up under the crest of Tunk Mountain. "That cleared area." I saw it, but not the stream he said runs across the property, a rare thing in this country. "The gun," he said, motioning to the sign Debbie had set up, advertising it for $35. I got out the shoe box it was in. "She says a spring needs to be repaired," I said. "Yes, the reload spring," he said, looking into an envelope that contained the old part. "I can fix it. How about $30?" m selling it for a friend," I explained. "OK." He smiled and handed me $35 that he already had folded in his palm. A bespectacled man, lean with time and the rigors of these cold mountains, had passed by once to look at my goods, then returned as the afternoon wore down. He wanted a new saddle blanket, of which I had two, each $25. He had a $20 bill and a finely etched concha from a bridle. Would I take it for $5 in trade? I looked at the button-like concha, amazed at the workmanship, the delicate patterns as puzzling as those on the bit of rug in "Of Human Bondage" that W. Somerset Maugham realized meant "There is no 'meaning' to Life: It's undecipherable forevermore." We traded. DEBBIE and Justus returned in midafternoon. She hadn't found Opal, but was cheered that I'd sold so many of her peacock plumes and the gun. Then it was my turn to meander the circles of fantastic rigs and fanciful humanity. Some were folks I'd seen before at such gatherings, folks who hadn't exactly become friends, but who wanted to tell me they'd moved or borne children or switched trades or professions or creative endeavors. As they intermingled and bargained, feasted, danced (and many would stay up all night in philosophical discussions), they made a grand clatter that shouldered its way up past the tree line and over these mountains. I was reminded of what one Barter Faire originator had told me of this semiannual event: "It's a spiritual essence; I want people to go away with a feeling of rebirth." They do.