1989 kawasaki 650sx help

[standupguy3]

I have a 1989 kawasaki 650sx stand up that it currently not working. It should be up and going in a few days after i take the carb off and rebuild it and mess with the starter. But my main question is what to do to give me some extra power, it was three years ago since we put anything new in it and we put a new impeller and a new top end in it. So i guess the next thing to do would be to put a new exhaust on it. What would be the best one for it and where could i get one? And what would be the next best thing to get some extra power. And i was also looking to put a new set of handlebar on it, can anyone suggest a good set and where to get them?

Thanks for any help.