Well, it ain't pretty, but it will hold me over for a year or more until I get the reupholster job from Shelby. I bought a salvage pilot seat for a C-150H from Dawson. The cost from Dawson -- $163 including shipping.
Took the seat back off (two screws, washers and nuts), bolted it on to my seat to replace the busted seat back, and presto -- a servicable seat. Now I have a complete pilot seat, and 1-1/2 passenger seat -- with usable spare parts -- for use when it comes time to reupholster. In the meantime, I'll cover this one with a cheap automotive slip cover.