Technical 1955 Oldsmobile rear seat differences

I am on the hunt for seats for my 55 Olds 88. It’s a 2 door sedan. My question is will rear seats from another model (hardtop, 4 door, convertible) fit? Thanks in advance.

 

Cross 4 door seats off your list, They won't flip forward for rear seat access.

 

Small Buick from 54 to 56 should work since they are built on a similar body,not sure if a Roadmaster or 98 would work since it was built on a similar body as a Caddy.