You can call Cat rece dept to get one, the price is usually a bit high imo, but they're gone through pretty well.
There is one in eagle CO for 6k that seems to be in good shape, haven't heard it run but it looks pretty clean.
Not sure what top speed is on these, mine is pretty slow as top speed goes, but it still has the original race weights in it that don't top out worth a crap far as I can tell. I just use it for learning new stuff/spare sled, it's fun to ride but I can't see keeping it as my main sled. Maybe if mine ran better I'd have a better opinion of it though.