Welcome A few things 1) this is what this coin is supposed to be http://www.wildwinds.com/coins/greece/lucania/thourioi/i.html 2) Can you weigh it and measure it? 3) you should re post it in the Ancients forum to see if there are any opinions on authenticity. Personally, I’m leaning towards fake because the toning looks unrealistic and the edge appears to have a seam filed down. I could be way off though.
You should check to see if it might be a BM Ready electrotype which would make it a bit more valuable than a common false piece.