If you find an OD trans make sure it is as complete as possible.
Yes, some of the components from other MFG's will fit but there are some differences. The solenoids from the later Saganaw/BW OD's have a smaller diameter opening where it mounts to the unit. You can get a Ford, Rambler, or other's govenor but the drive gear will be different. Many of the internal components are the same such as the planetary set and the roller clutch but you cannot take the OD housing from another MFG and bolt it onto a Chevy trans.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine