best tube integrated under $5000 ?

The Leben CS600 is a great sounding integrated tube amp. One of the best integrated tube amps, I’ve heard. They play really nice with Harbeths and DeVores. They also have a unique retro look that grows on you.  You can probably can find a used one for less than $5k.

" I would look at the Raven Osprey great sounding integrated. "

True.  Or hold out for the upcoming Raven Eagle integrated. 

Audio note Meishu as has been mentioned already. I have heard the Westminsters with the audio note (Japan) ongaku. One of the most memorable listening experiences I have ever had.

ARC VSI60, well below 5K used...........stunning with moderately efficient speakers

You should be able to find some here:

http://www.sophiaelectric.com