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I'm also going with The Reveal on this one as it appears identical to your other question.
We have Counterfeit Cash and Magical Counterfeiting, but neither article mentions a page for non-magical counterfeiting of valuables besides cash, so I don't think we have it yet.
EDIT: We do have Expensive Glass of Crap if the scammers successfully pass off a cheap vintage for a more valuable one.
Edited by MetaFour
A winery sells what proports to be wine from the 1930's. However, lab results prove it couldn't possibly be from any earlier than 1957. (It's probably much more recsnt than 1957, but no more precise evidence is ever told to the audience.)
Edited by Someone1981