Currently using a Reptisun 10.0 UVB bulb for his enclosure (http://www.amazon.com/Zoo-Med-ReptiS.../dp/B00061V53Y). It gets good coverage since he is still on the smaller side and, in turn, in a smaller enclosure. When I build him his big enclosure, her's going to be getting huge tube bulbs lining the back of the cage.
Update on his situation since it's been a while since I initially posted this: he seems to be growing/doing fine. His under bite hasn't gotten worse (at least not that I've noticed) and he's eating and shedding normally. He seems to have mellowed out a bit and doesn't seem to be effected by his jaw.
Here's a pic of him I took today:
Talked to the shop I got him from (didn't order from a breeder) and they didn't seem to think it was anything to worry about. Just wanted to get a third party opinion.