Primaluna tube integrated amps are within your budget. Some one also mentioned a Bob Carver tube amp here 275 Crimson which is 75 watts per channel and going for $2500, that would drive those Focals very well. But you'd also need to pair it with a preamplifier.
I would highly suggest the bigger two PrimaLuna integrated with the KT 150 tubes for the sound you are looking for. They are very lush and majestic sounding amps.
I would highly suggest the bigger two PrimaLuna integrated with the KT 150 tubes for the sound you are looking for. They are very lush and majestic sounding amps.