more than likely it is a sc-10 rear suspension unless it has three
shocks on the rear then it is the c-7 the sc-10 has 10" of travel where the c-7 has 6 you want to have around 2"-3" of sag when you are sitting on the sled and as far as the skis are concerned, the camoplast skis are decent, but for that muscle sled of yours i would invest in a set of ski-doo flex or precision skis they are well worth the money. i would leave the can stock with that motor i really don't think extra weight will be a problem
good luck and hang on!!!