Year's ago same situation 2dr car looking for a roof skin. I looked through the part's book and everything i found had the same part number 2dr to 4dr on the roof skin numbers.
If the Polara/Monaco share the same handle as the Fury line my 70 wagon I used 1st Gen Ram door handles exact same housing just had to swap the mechanism. And those repops are way cheaper then the C body or NOS one's that I've seen so far.
I used 1st gen Dodge Ram 81 to 93 outside door handles on my 70 Fury wagon. The push button mechanism needs to be swapped to your old one But perfect fit.