I should add.

VeloBase.com can be used to search components by decade.
Search feature near top left of page.
Pick your component,
scroll to bottom of search,
Select preferred decade.

Sorry if redundant.

I recommend finding components best from:
1. Become a paid Forum user and make your requests in the C&V Sales sub-forum,
that's where the sellers hang.
2. Just participate in C&V trading thread.
3. other places that may be local with used parts you can see and touch. USA is community co-operatives
4. online places, buying from people with a history and credibility.
5. Luck.
6. Donor bikes. (but tough for 50's bikes)