bwhitsonjr, I recommend that you read the thread on Pastor Jim's scooter, since it will help to familiarize you.
On his previous scooter (which was 50cc), the stock airbox and muffler were terribly restrictive, so I welded a less restrictive muffler on and used a pod air filter. I increased the slow and main jets to compensate.
When he got his 250, we looked at the stock airbox and decided that it wasn't too restrictive and chose to keep it in place. That said, a pod filter would be an easy install on your scooter, rather than sourcing the original airbox.
Page three of my thread on Pastor Jim's 250 shows that I installed a ZX-6 muffler. The stock muffler was heavy, and it had a catalytic converter inside that was quite restrictive. Jets are very easy to find for that carb. Slow jet:
http://jetsrus.com/a_jets_by_carbure...99103-MA1.html Main jet:
http://jetsrus.com/a_jets_by_carbure...und_28-xxx.htm
Please measure the OD of your carb inlet, and let us know the size in millimetres. We can probably guide you towards a pod from there.