Saginaw Overdrive stuff

I'm looking for a supplier {or the dead ones in your back yard} of OD pieces for GM 3 speed manual transmissions. These are a stock GM option, normally in cars and light trucks. The overdrive in question was supplied {normally} behind 3 speed saginaw, 7 bolt side cover, syncro tranmission. I'm interested in solinoids,govenors & misc. hardware.
Randy