Rep. Jack F. Kemp (R) of New York threw a completed policy pass after Heritage hiked him the ball. The Republican Platform Committee at Dallas adopted his plan last summer to sell public housing at a substantial discount to tenants. Billed as a ''right to buy'' plan, it allows tenant groups to bypass local authorities and make a purchase directly through the federal Housing and Urban Development Department. Kemp is the author of a philosophically similar bill on urban enterprise zones, which is stalled in Congress. It offers tax breaks for urban development in run-down areas.
Both ''private sector'' ideas originated with Stuart M. Butler, a British scholar with Heritage. The timely adoption of the public-housing plan in Dallas typifies the speed with which a Heritage idea can find its way to a policy conclusion. Heritage tossed a host of ideas to various Republican leaders before the convention and then ran with ones that seemed promising, none more so than Butler's and Kemp's. It dovetails neatly with the Reagan goal of reducing the role of the federal government, and it meets the tactical campaign need of offering something to the poor - demonstrating exactly the kind of policy maneuvering at which Heritage excels.