First, if you find the auction of the coin in question, please don't steal it!

I think I got the identification, or at least somewhat so. I'm almost sure that its one of the first four coins listed here:
http://www.wildwinds.com/coins/ric/constans/i.htmlBut I feel it most resembles the first one. So, ancient folks, do you agree? Or have I missed the ballpark and hit a soccer player?

