I'm not sure they take stamps. I had a couple with the coins I took in, but I think he told me he doesn't take them. Call them, they're very nice.
You would probably need to take them in for appraisal. Stamps can be more variable than currency. Arlington Coins sometimes answers here, but i expect they'd need more details.
Larry, we may purchase unused sheets of stamps, but are not purchasing used or loose stamps at this time. - SL @ArlingtonCoins
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