I don't have any GTS experience, but this guy:
http://bornagainfairings.com/Has lots of experience with fairings and has a shop full of spare bodywork he picks up. He fixed a sidepanel on my BMW and while I was there some guy came and picked up a set of bodywork for a 2-stroke Yamaha RZ500 that looked

From your description he could probably fix what you've got.