Sure you can. Silencers/mufflers are (almost) all the same. All the two stroke requires is the expansion chamber in the pipe to reflect pressure waves back to the combustion chamber. Granted, the silencer provides a little back-pressure of its own, but any four stroke muffler will provide the same.
It seems there are a lot of choices out there for sportbike exhausts... I bet you'll end up with something pretty cool-looking.