Any chance for a limited number of Ta152s? They started service right around the beginning of 1945 (which is close to this setup) and even so could sub for late-model Doras where they were testing 30mm hub-guns and so forth.
(*insert praying emoticon here*)
EDIT: You could drop the 190A-5s and shift the 190A-8s down to that slot, move doras to the 190a8 slot, then put the ta152 in the doras' slot