I don't have much experience with the 5.0, but I own a pair of 5.3 which I really enjoyed with a Cayin TA-30. I did try a few SS options, the favorite of those being a SimAudio Moon i-3, but I kept going back to tubes. In your price range, I would recommend the Cayin or the similar PrimaLuna ProLogue series.
If you're set on using mono amplifiers, used Quicksilver Mini-Mites are available well under your price target.
Good luck!
If you're set on using mono amplifiers, used Quicksilver Mini-Mites are available well under your price target.
Good luck!