https://www.ebay.co.uk/itm/254319712890
"Authentic coin", countermark described as "fantasy". Why anyone would pay anything for this I don't know. It's not even a good fantasy - the S.F. Maria Theresa thalers have only been minted since 1853 - looks like a 20th century Vienna coin. The guy is selling a lot of other countermarked "fantasies".
Wonder where they come from...
...ah.