I think a list like this is REALLY needed! I have trouble trying to find parts online a lot of the times.
Game on grafix
mikes arcade
Arcade Shop
T-molding.com
Gamemolding.com
groovygamegear.com
thearcadeboneyard.com
Pinballlife.com
pbresource.com
I think you can remove Radio Shack at this point. I found a few sites, but seem to have lost most of them.
Im looking for the site that had all the coin door plastics.