If any of their vendors sell stamps, they can probably put you in touch with them to get your questions answered. There's also a guy on US 1 not far from Barn Yard Flea Market that sells stamps and coins. He might be able to help you. Can't remember the name of his shop but it's on the left going out of Columbia towards the Barn Yard. He's in a really old brick building. He has a sign out for coins, stamps.
This is a mall with vendors who may or may not be present but they do have knowledgeable workers at the main counter who may be able to help you
I have no idea about that.
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