If you can't find a wrx that was owned by some old lady and left completely stock, avoid it. We see more Subarus coming into the shop I work at, with problems, than pretty much any other car. If you want good snow performance my best answer for anything under 10 is to find a well maintained, maintenance up to date, audi c4 s4 or s6. In terms of performance they will destroy any Subaru in snow. And as long as they haven't been neglected, they will be extremely reliable. We have a guy that uses our shop, he has over 300k miles on his s6. Stock tranny, 2nd clutch, and just now replaced the turbo. He's been coming to us for years any only getting the usual maintenance work done. We see a lot of Japanese and European cars, and those audis are the best combo of reliability, snow performance, and overall tank like build quality.
Other choice would be a mint e30 325ix. Not quite as quick but better balance and more fun in the dry, also insanely reliable when they're not neglected.