Easier to find an MSP and just buy it. There's a lot more than just slapping on the turbo to boosting your P5. If you're set on sticking with the wagon, the easiest way to go about it is to find a wrecked MSP to vulture parts off of.
If money's no object, I'd buy a Garrett GT28R turbo, a haltech ECU and a Quaife differential and go to town!