No, the Museun Shop does not sell Mogan dollars. There is a good coin shop directly across the street that may have them - Northern Nevada Coin.
Im not sure about coin sales although the staff there spent a good hour w us showing coins, discussing the history and security of the mint. I purchased a pressed silver piece for 60 dollars as a memento and for benefit of the museum. You'd probably best call and inquire. Its a great monument to US history w knowledgable, generous staff!!
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