Here's one to consider,,,Olympus E-PL1. Sells for $540 with 14-42mm lens for less than $600. You can use other lenses from pani, nikon or leica. Looks like you need a fast lens (f2.8) for that kind of work.
Or you can get a used nikon d40 and get a used prime lens (f1.4) for less than $200. If you use fast lens and shoot from good angles, you may not need flash.