This coin has been a bane! I don't have enough letters to make out who is shown on the obverse and reverse. I looked through 1,500 coins and like 150 pages of results looking for this one. Any help is appreciated. The coin is much better in hand than the flat image the portrays.
I was able to track down a similar one with the same inscription, this should help you get on on the right track. ΚΑΙΣΑΡΟΣ ΣΕΒΑΣΤΟΥ https://rpc.ashmus.ox.ac.uk/coins/1/1711
Well, that made a quick job of things. There are quite a few different portrait designs in this listing. I'm glad that my example is the higher style portraits. I truly like the flowing hair on mine. URI https://rpc.ashmus.ox.ac.uk/coins/1/1718json ttl rdf xml Volume I Number 1718 Province Thrace Region Thrace City Uncertain mint of Thrace Reign Rhoemetalkes I Person (obv.) Rhoemetalkes I (king) Person (rev.) Augustus Obverse inscription ΒΑΣΙΛΕΩΣ ΡΟΙΜΗΤΑΛΚΟΥ Obverse design diademed head of Rhoemetalces, right Reverse inscription ΚΑΙΣΑΡΟΣ ΣΕΒΑΣΤΟΥ Reverse design bare head of Augustus, right