Another alternative is to have a Turbo custom built. I'm not sure whereabouts you are, but in QLD there are a few good workshops that can buid you a brand new turbo using your specs for a very competitive price
I'm looking to buy an R32 GTS-T, GTR radiator for my brothers RB20 S13.
Would prefer to pick up from Brisbane, QLD, but am happy to pay for postage.
Thanks guys