Slinger- It is a K&N model #RC-2540. I ordered it direct from K&N online. It was $23.
Jarek- I ordered the carb from Moped Hospital, mhr-usa.com. I got it with one of their performance packs, but it looks like it is $130 by itself. I also got a full set of main jets from provoscooter, they are $4 each.