Your best bet is to have them straightened at a machine shop. If you know someone with a hydraulic press, that works too. It doesn't have to be real fancy. I've straightened out many rails on mine.
Also, check to see if the rear pivot links are not bent. I was just working on an '01 Edge X, which had, what appeared to be bent rails. A closer look showed that the rear lower pivot link was bent, throwing the whold skid off-square. Other that that, you can find a good deal on complete skidframes at Haydays in Minneapolis in the fall. New rails are $200 ea....ouch!
Unless the machine was totally destroyed, the rails are usually straighten-able.
There are a frew Xtra-12's on ebay, type in Polaris suspension in the search box, and you'll find a bunch. Shipping is usually expensive on a complete skidframe, but sometimes you can get the seller to dismantle it, or just ship the pieces you need.
A forum community dedicated to snowmobile owners and enthusiasts. Come join the discussion about performance, troubleshooting, trails, maintenance, riding tips, modifications, classifieds, accessories, and more!