I don't know about interchangeability... Try browsing the Polaris site for the part numbers you need..
Normally people replace stock exhaust with aftermarket for performance gains and part of this change is replacing the jets in the carbs and tuning the clutch to take advantage of the increase in power. If you are just getting the sled to run then stock is a better choice. Used off of ebay is your most economical bet.
94 Polaris XLT - XTRA 10, Ski Skins, 3" riser
97 Polaris Ultra
96 Ski Doo Formula III 600 (sold)
97 Polaris XLT Limited - XTRA 12 (My Son's)
80 Kawasaki Intruder (sold)
72 Polaris 340 Colt SS (sold)