If your a collector I would keep it and add it to your collection. A find like that would be a great addition. If your not I would go to there or four different dealers. Some dealers aren't as reputable as others and some know of private collectors that are looking for specific coin. That been said one of the dealer I would checkout is the Arlington Watch and Coin shop. He has always been very good to me and has been fair and honest.
Hey man, it's up to you. Selling it might make a quick buck, but holding onto it could possibly have it gain value. However, if more are discovered, it could potentially lower the value.
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