She should be. Don't let her worry about what a bunch of coin nuts like this says. A lot of us worry about everything..
Chick out my profile picture, it is a counter stamped stone mountain half. To help the sell of this coin to fund the work on the St. Mt granite memorial, these coins were distributed in the southern states and stamped with the locations of the agencies. When my father first found this coin among my late uncle's collection, he thought it had been damaged and worthless however the counter stamp made this specimen more desirable. The NC edition is said to be more rare than other states and I am just now interested in obtaining a value and maybe selling the coin.
If you check the auction records you can probably find an approximate value, but I don't think you can sell anything through this message board. All of the counterstamped SM coins are rare and only PCGS certifies them. I believe they have certified fewer than 125 counterstamped coins. These were auctioned and the serial number was used to create interest and perceived rarity. Even more rare would be a counterstamped coin with a serial number, state letters, and the letters S.L., G.L., or UDC. North Carolina coins are not the most rare. I believe the Texas counterstamped coins with overstruck initials will be the most rare.