Foxmoth - the original two-seater Spitfire VIII is still around, with Jack Erickson in the States. The Irish Air Corps two-seaters were all MkIXs, and several of those are still around (ML407, MJ627, PV202/IAC 161).
IT's not known for sure how many two-seaters the Russians modified, but they differed only in having the rear seat and instruments fitted. The forward cockpits and fuel tanks were not altered.