like so many other things, the Confidential Bulletins and other factory documents rarely show up on eBay. Rarely seen at general old car shows prior to COVID-19, this lack of visitility give the impression that our cars have to be all but extinct, impossible to find parts for and there isn't a club or other "support group" for owners. This is not true for those of us who own cars, but this is what Barbara & I heard from spectators we talked to at the shows we took our 1952 HJ Corsair deLuxe to after moving to WA and before COVID shut things down. These days, unfamiliar sellers tend to start high, and if there are no responses they can go down until they hit the proper price points.
Best prices for anything K-F seem to be member to member sales or at major club meets like National Conventions.