If you want something below $1k, you might want to consider a 2 person band or a soloist. $1k split 3 ways isn't much, so I think it'd be hard to find a band, especially if you factor in the sound system (I think most bands charge an additional fee if your hotel doesn't provide a good sound system).
So far, I've considered ShiLi & Adi and Vetta Quartet, but the prices are a little over my budget for live entertainment. They're pretty good though!