Okay, how about using the name "Scythia Pontica" for that region around Olbia? The name Pontic indicates usually to the Black Sea, and sometimes Olbia in Scythia was called as Pontic Olbia, so that it can be separated to Olbia in Sardinia, and some other places with same name. http://en.wikipedia.org/wiki/Pontic_Olbia
Luc.