That is the mtn can. It is loud. If you like the sled it is an easy thing to swap out and should not be a deal breaker. I would ask if the seller has the stock exhaust can still. It will be worth having, probably will get some rpms and hp back over the mtn can.
Stock ones show up every now and then - I think you should be able to find one over the summer easy. Or just offer up your GGB as a trade to someone snowchecking. I wouldn't let the can hold up the deal if you like everything else about the sled.