Looking for a 1976 A-body A38 police certified speedometer

Oooh thats a rare one. I'm curious if anyone has one ! There is a rectangular "C" body 140 mph speedo ('68-'70? ) that can be trimmed down to fit. Not an exact swap but 140 mph vs 120 mph on the "A" body one. Somewhere there's a Duster, maybe on FABO if it still exists, with this conversion I did back in the 80's. Best of luck in your search !