With mention of Calder, I'm assuming you're in Melbourne, right? In that case I can't help you out with a dealership, 'cause I simply wouldn't have a clue considering I'm in Sydney. Try grabbing a copy of HPI, Zoom, or some other local magazine and ring up a few dealers who advertise to see what they'l do for you. I think you'd probably be able to find stuff cheaper if you do your own shopping, because the dealers will probably want to add their own margin to whatever they order for you.
I doubt you'd beat an R33 GTSt, even if it's standard - unfortunately the Stagea is 200+ kilos heavier than a Skyline, and that is its biggest burden and probably the only thing all Stagea owners hate about their cars.
If you were to drag race when at Calder, then you might have a good chance of getting the R33 off the line (due to traction), but beyond that the weight starts to take its toll. Around a track wouldn't be much different, and quite probably worse the further you got around the track...