Actually folks have put the 6 spoke '93 down Legacy Turbo / Legacy OutBack rims over '02 WRX Brakes, but the calipers had to be ground down for clearance - so they can fit with modifications.
You could just get a set of 15" Rally rims, which are usually made to clear 4pots if you do not want to grind the calipers down.
I have a set of 15" Enkei Rally rims & they do clear 4-pots by a hair, they also weigh just 12lbs each so they are pretty dam light!