Used guns in your price range that are common and/or popular:
Empire Axe, Invert/Empire Mini, Eclipse Ego 07/08/09, Dye Matrix 08/09...
I am not familiar with Bob Long pricing, but there are certainly some older Marq series and Intimidators that you could afford. And FYI, Angel has been out of business awhile, so they have mostly gone to collectors.
It all depends on want you are planning to do, monthly rec ball, tournies, other? Maybe head down to the local field and check out everyones gear before spending the cash.
I got back into the sport last spring, and started with an Ego 08. It was in good shape and performed as well as most other tournament level guns, but only cost me ~$400. Remember to budget for a tank/hopper/pack, and paint!
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