There are a lot of options, many of which will meet some track requirements.
If yours is loud, and it wasn’t before, repacking it may help a lot. I would only buy one which could be disassembled and repacked (may have to drill and replace rivets)
Recognize that quite a bit of the noise you hear is likely coming from the intake end of the motor. That will be true if you have an open air filter. Unless you are running a noise-reducing airbox, there are ways to muffle the intake pulse sounds, primarily by using a surround which is only open on the seat side or the back.
Good luck!