The Peachtree should be a great fit. I have a PS Audio Sprout100, which is about that price brand new. Small but mighty. Also good with 4 ohm speakers. I can also vouch for Audiolab 6000a, which would give you 75w at 4 ohms. Or if you want something more vintage, I love the Sansui AU-999, an absolute workhorse. Beautiful warm sound, 4 ohm compatible.
So many options! Good luck.