First off Copterdoc - Welcome to the Bolt!
Page 1-19 of this 1948-51 Chevrolet Truck Shop Manual should be the same info regarding your GMC rear door latch hardware.
Click next page as the information continues on following pages.
You can find more parts information that relates to your topic
HERE. Again, it’s a Chevy parts book, but these parts should be identical to the GMC parts.
As for as parts sources, I’m not familiar with any vendors that reproduce those parts. You can search the web for folks offering used parts, or post an ad in our
Truck Parts Wanted forum.
Others should be along to offer more info and help.
