Anybody know where to find a substitute parts database...

I don't know of a data base, but I can give a little advise. As is with many newer vehicles, old vehicles had a lot of the same parts in that era all engine of the same size will work. Obviously. Galaxie is a big car and most big car part work with the other big fords. I'm thinking rear ends, transmissions, alternator, radiators, etc. The best thing to do is find and old junk yard with older guys working there and make friends. These old guys that have been working in a yard all there life know everything about part swapping. Sometimes just being a frequent and polite customer will get you a long ways.