I was in a very similar position about 7 years ago, looking for a used amplifier that would easily drive Magnepan 1.7s. I tried a Bryston B60, Hegel H2O, and a Devialet Expert 200. They all worked well and sounded very good, and they are all in your price range used. My preference, and what I’ve stuck with, was the Devialet. But that’s me. You’ll have your own personal preference. Each of these units was about 5 or 6 years old when I bought them, and they all were very dependable. I’m still using the Bryston also.
enjoy!