TΡIΠOΛ… = Tripolis (or the Tripolitanians). Because the obverse shows the turreted head of Tyche, I suppose it's from Phoenicia. We have very few coins from there in the Numista catalogue. There are not many more in the wildwinds database (section “CITY AND SEMI-AUTONOMOUS COINAGE” at the top of the page). Yours doesn't seem to be in there.
As for the countermark, I don't know its origin, i.e. whether it's Phoenician or Greek or Roman…
EDIT — Looks like it's Tripolis in Lydia. Look for BMC 43 to 45 on this wildwinds page.
