Not sure what the fee is, but what I can tell you is that Bulgaria is in Group 2, which means you don't need to get your tourist visa in advance. You will be issued the visa upon arrival.
Unless you plan to move here to request residency, in which case you have to go to a Bolivian consulate near you and get a Visa de Objeto Determinado (not a tourist visa) and the price for that is $85.
