West coast mirrors for C 30?

[old Chevy guy]

Ive been fixing my truck for a while now and its going to get painted on Monday. I bought some mirrors from a board member awhile ago but now Im not loving them so much any more. Ive been searching online but cant find period correct replacement west coast mirrors anywhere. Does anybody know where I can buy some good correct or even just well fitting brackets for our trucks? There's some west coast mirror brackets on Amazon but I have no way to know if they will fit good or not.