A used McCormack DNA-0.5 or 0.5 deluxe would work very well and be well within your price range. McCormack has a reputation of being the tube lover's solid state amp, so take that for what it's worth. I'm using a DNA-0.5 Rev. A with a pair of 5.3s and it's a pretty sweet combo. I also like the Pass Labs and Odyssey recommendations. Best of luck.
Tim
Tim