162 Kaproni KB-5 (avail. 1/36) - better name is KB Chuchuliga - KB-5 Chuchuliga III appeared only in 1939
http://www.airwar.ru/enc/spyww2/kb5.html , earlier there was KB-4 Chuchuliga II in 1938
http://www.airwar.ru/enc/spyww2/kb4.html, earlier KB-2A Chuchuliga available in 1936, although the latter one was a trainer
http://www.airwar.ru/enc/other1/kb2.html.
If we'd like to create a bomber before 1937 (when Bulgaria officially created air force) there could be added
U-1, which was a copy of DFW C.V
https://en.wikipedia.org/wiki/DFW_C.V , or
Potez XVII https://en.wikipedia.org/wiki/Potez_15 https://commons.wikimedia.org/wiki/F...aria,_1928.jpg. They were used secretly during some manoeuvres with 10 kg bombs. Potez could also serve as a spotter. Polish OOb uses similar (newer) Potez XXV.