OK, doing some research this morning and rechecking my measurements. 2.5" high when measured vertically, 2.75" when measured across face with a football shaped valve stem hole. Also has a flat clip ring, no raised lip.
Looks like these are 67 Corvette and 69 Z28 1st design trim rings that matches part number 3901703. Don't see any recent Ebay items that match. With these needing restoration, value is tougher to nail down.
I guess the best thing is to throw them up on Ebay today and see what they bring.
