As others have stated, there are many good suppliers of replacement parts for those parts that are available. Sometimes you may find that certain parts are not available through normal channels. When that happened during my restoration I followed this method:
1. Using the factory assembly manual, locate the part number..
2. Using the GM parts wiki online, learn what model year and model the part number was used on and any supersessions to the part number. That helps when trying to find used parts at salvage yards
3. Search online , google, eBay, etc..


One of the many places I've used to find NOS parts is parts voice. Check it out.

http://www.gmpartswiki.com/

https://www.partsvoice.com/

Ron - - Dusty53
1954 Chevy 3604
In the Gallery Forum
"You can't dance with the Devil and then wonder why you're still in Hell."
"They will forget what you've said, and they will forget what you have done but they will never forget the way you made them feel."