aper, thank you, I was able to find some labelled maps - some only with cyrillic labels, but I cross-referenced them with transcriptions and worked out which municipality is which :) I'm about halfway done now.
But I'd like you to tell me one thing: are Burgas and Sozopol municipalities, on the far right in green bonus, correct? I found "conflicting" maps - the two linked in this topic say it's the way I currently made it, but for example this one:
http://en.wikipedia.org/wiki/Municipalities_of_Bulgaria#Burgas_Province says that a large part of Sozopol on my map should be a part of Burgas.