Correct Super Stock Seats?

I do know the seats in A100 were made by Bostrum, and they are still in business.
Gary Ball, In. is into SS early B car and does a lot interior for real cars and tributes of such. He says he makes his own seat frame and thus seats, and as he says darn hard to find original A100 seat frames. His seats fold.
I have had peeps tell me they have seen A100 seats that some are fixed. I have NO idea.
I used those SmittyBilt early CJ 5 seats because they work for me and a lot of other guys use them.
I have NO hound in the race.