Gergis, Troas, AR obol. 9mm, 0.55 g. ca 350-300 BC. 

Wreathed head of Sibyl Herophile facing slightly right
GER above sphinx seated right.

Lazzarini fig. 5. Apparently unpublished as obol, but several have been sold at auction since 2007. 

With permission of Numismatik Naumann Auction 41, Lot 233, March 2016.