I'm personally tired of paying store prices for f/t, so I was looking to go to my first reptile show to pick some up for hopefully cheaper. This is my first reptile show, so I would appreciate any input as to how much f/t rats run there.

I've had trouble finding a good source of rats around me (northern virginia/ school in central VA). If anyone around the DC area knows a good place to get some, ideally for a good price, that would also be appreciated!

Btw, I am planning on going to the Manassas, VA show.
http://www.mdreptilefarm.com/shows/va/nva.asp

My BP is currently eating a large mouse every 5 days like clockwork. He's a big eater, less than a year old, just north of 2 feet long, and I'm trying to get my hands on a scale so I can get a number on his weight so I can get his food in the 10-15% range. Idk what size rat he would require (as I have only fed mice so far), so any help on that would be appreciated as well! I have pictures of him in my gallery for comparison.

Lots of text, but basically:
How much do f/t rats cost at reptile shows?
What size rat might my BP need? <<<extra credit