Those are rare BTW. Mine was badly scratched and faded. I first tried to put it in my drill press and polish it, but it's not a simple plastic, exactly, think it's something like bakelite? It has an unusual texture and didn't polish well. I looked through all the usual sources and couldn't find a replacement so I put an aftermarket one on.
--
1981 F-250 Custom. 6.6L V8, 4 barrel Holley carb, ARA aftermarket A/C.