I thought the Japanese aircraft ATD-X or something was an own design with thrust vectoring and stealth similar to F-22 not actually an F-22. I don't think F-22 was release to Japan because of security risk, how Japan is only a spit away from China. I read somewhere China stole tech through Japan before.
If going by the logic of not selling weapons to past enemies then I'm for banning weapon sales to UK, Fance, Germany, Italy, Spain, Cananda..... not being sarcastic I just really don't wanna see these coutnries benefit from high tech us weapons hahahaha
Back to the SU-34 I don't think its practical, even if RAAF fit them with Western avionics there's the matters of spare wheels, tyres, pylons, external fuel tanks, wires and cables.. etc that needs to be bought from a different source than the curent fleet. Assuming that RAAF SU-34 uses western engines, thats where I see the main logistic problem.
Anyone know if integrating Western targetting systems with Russian flight control and navigation been tried anywhere?