@lachlan I'll take you up on the intercooler, VF23 and ECU(s) depending on price.
@ginganinja is selling a HKS hi-power catback and I can vouch for these exhausts. Really, really nice. You may have trouble finding a downpipe as most of the ones available suit a GD chassiss. (They are single scroll and mount to the gear box, but they are slightly longer in overall length and make it a pain to fit to a GC catback).
NZKW do the black silicon intakes.
Don't know about the turbos - I sourced a brand new VF for $1,000. If you have the money, you should be able to pick up a VF between 1-2k or an aftermarket one that will fit the factory location in the same price range.