For 10k you could most probably import yourself a nice, clean, newer NA R33 Sedan (might not be eligible though as it might not meet power to weight requirements... will have to double check). Failing that a turbo R33 sedan can be imported for sure, and no one ever bids on em at auction, so you'll get em dirt cheap.
Hardly any R32 GTS25's came into the country under the old import scheme, so chances of finding one are rare, but they might still meet the power to weight requirements of SEVS, so you could always look at importing your own.
Failing that, tell your step brother to bring back a car from canada (they still have the 15yr rule over there and can import a lot of nice stuff). Our canadian website should give you an idea of what they can get