Istros, Thrace. AR drachm. 

Two male heads facing, the right inverted.
ISTRIH, sea-eagle left on dolphin, L beneath the 
eagle's tail. 

Talmatchi, "Consideratii.." II, 17. 
Note: this type is also known as a Barbaric imitation
(Canarache 404).

Image taken from the Talmatchi article.

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