Can someone suggest a lush tube integrated under $3000 used

Quicksilver integrated. Great customer service.

http://quicksilveraudio.com/products/integrated-amplifier/

@paulcreed ,
I would suggest you reach out to Auric Audio. They may be able to build you what you want near your budget target. Excellent quality work and customer service.Let him know what you desire. Choice of transformers, capacitors, resistors and wire can tailor the sonic signature of an amplifier.
Charles

Quickie EL84 would be really interesting to hear. OP said his speaker is not efficient though. Cary SLI-80 was the first that comes to mind. There are quite a few who perform upgrades to it, so there are always options to make it more neutral. In stock form it is said to be on the vintage (warm) side, as described here above.....

paulcreed- 20 watts is a concern with 6ohm 87db speaker even with there claim of high current.

You would drop that concern in a heartbeat if you were here for Chuxpona. We had some very inefficient 87dB monitors that were driven with some 100+ solid state watts at first because we couldn't believe the little Raven would be enough. When we switched amps to the Blackhawk those speakers came ALIVE! Anyone listening blind would swear the amps were reversed, they sounded so much better with the Raven.  

The owner was floored and wanted to see how loud they would go. "Is that as loud as it goes?" he asked. I never had to crank it like that with my Moabs, so just kept cranking until it was about 3/4. The sound was big and full and LOUD! 

I know it sounds crazy. The common wisdom keeps insisting watts are watts, no matter how many absolutely unbelievably compelling demonstrations proving it wrong. They just keep going. Like the freaking Energizer Bunny. No evidence. Proven wrong over and over again. Do a search. Read actual user comments. Lots of people have these with speakers like yours, power is simply not a problem.  

Oh and the room we were filling with volume? 17x24x9. Not small. And full of sound absorbing audiophiles at the time. I believe this is written up in my Chuxpona review as well.

Conrad Johnson is the obvious one to look at.  There's the CAV-50 and nowadays the CAV45-S2.