Muffler Baffles?

[Scheezo]

I got my bike used (2002) a few weeks ago and the muffler is kind of loud. The salesman said the previous owner must have taken the baffles out of it. I was thinking of getting a new muffler and was looking on JC Whitney's site and found that they sell baffles. I don't know much about mufflers so I was wondering if y'all could help me. Is it possible just to put the baffles back in? Are these the baffles I need - http://www.jcwhitney.com/internal-baffles/p2006266.jcwx?

Any help or insight is greatly appreciated! Thank you so much!