To answer your question.... No... The car is like 3-4 life-cycles behind as far as what OFNA has released since the OB4... Parts replacement will also be super hard to find... Your best bet is to sell it and step up to one of the current touring cars that are on the market right now... You can't go wrong with either a Mugen MTX4, Kyosho RRR, Serpent 720, Huddy's NT1 or the TM G4S... There's a thread here on RC Tech that you can try to sell your OB4 or you can also try Ebay or ask your lhs to try to sell it for you... You will never get what you paid for it, so you may even end up having to almost give the car away in order to sell it...
Just being honest...
RC_Alan