Suggestions for a tube pre and power amp

1. @lals   you have some very good recommendations to consider!  
2. I recommend a Conrad Johnson Premier 17ls pre and a C-J LP66S amp.  Both are tube and work very well with low impedance high efficiency speakers.  Keep an eye open in this site for unit's on sale!
3. I believe you would enjoy C- J equipment!

This preamp is a CLASSIC and a screaming bargain. Read up about it -- it’s legendary. 

https://www.usaudiomart.com/details/650263291-dehavilland-ultraverve-iii/

One key thing about it is that the 6SN7 tube is at the heart of it. DeHavilland’s Chaffee built the design around this octal dual-triode rather than the more common 12AX7 family, and the 6SN7 has a character that is uniquely satisfying — tonal density, spatial generosity, and a midrange presence that isn’t clinical nor artificially warm. 

The unit’s circuit topology is deliberately simple and direct — minimal gain stages, no unnecessary buffering — which tends to preserve the integrity of the signal and keep the noise floor low. 

Respectfully, may I suggest that you have it backwards. After going from all solid-state to all tube components, I would recommend a solid-state preamp and a tube amplifier (mono-blocs preferred, such as Quicksilver Mid Mono or above). The driver and power tubes in the amplifier are going to control the sound so get a good quality amp and buy some decent tubes.

I use a Vacuum Tube Audio SP 14 into a Mac 462 into VSA VR4 jr’s. The 462 has separate grounds for each impedance, so I can run the mid/treble on 8 ohm taps and 4 ohms on the bass unit. Like biamping with one amp. Power is not an issue.

If you don’t want as much heat, the newer generation of Pass Labs A/B amps are biased to produce a bunch of class A before switching to A/B. My Wilson’s are the same efficiency as yours plus they also drop impedance pretty low like yours. My 260.8 monos just love the Wilson’s. I tell you true, I can’t get the amps into A/B if I’m in the same room. The needles don’t even move. Great soundstage, strong control of bass with good detail without the “etched” sound that makes me crazy. I’m running a tube preamp too, the combo works really well.