https://www.grayandsons.com seems to have a bunch of used, but not sure how accurate their prices are in the current market. Inflation is here to stay
IMHO, they do tend to hold their value more that other pieces of jewelry that tell time.
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01 Z Coupe, 5MT, SB, not much else
08 M3 Coupe, 6MT, JB, not much else
21 M2c Coupe ,DCT, SOM, not much else