A decent quadro is outta ya price range....the gaming cards are better at 2D drafting , the Quadro's better at rendering. How much time ya spend doing ecah should define ya decision.
If it's 2D, I'd get a 460 GTX. here's a factory overclocked one that fits ya budget.http://www.newegg.com/Product/Product.aspx?Item=N82E16814130571
If it's rendering, keep in mind the best card in ya price range only has 256 MBhttp://www.newegg.com/Product/Product.aspx?Item=N82E16814133273