Rich - I'll second WICruisers note about showing us what your upper latch piece looks like. Your lower plate sure needs a replacement or repair, but the upper may have problems too to identify before being able to help you answer your question.
On the lower catch latch plate assembly, it's listed in both the 1954 and 1957 Chevy Master Parts Books as fitting 1947-53 Commercial and Utility Trucks (except COE's). See screenshots below.
So any 1947-53 Chevy or GMC truck (other than COE's) can be a donor to replace yours. I hope a fellow Bolter can help you out. Best of luck!
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* I posted this info in your
Swap Meet ad in the hopes we can help you fix the problem.
