Rick, I've never heard of a Golden Gate thumb pick. I don't live at the end of the world, mind you, but one can see it from here. Dunlop, Martin, Fender... I think that's about it... but they're available in colors.
I'll ask around and see what I can find. Maybe Bill Nix (Somewhere in Iowa Guitars) will have them. I haven't been around to see him in a while.