recommend PRAT Integrated amplifiers (not Naim)

There are many good recommendations from other members.  If you are looking for PRAT as well as liquidity, clarity, staging/imaging, and a  light touch of “tube-like” warmth I recommend a per-owned Burmester 082.  There is one on AG just under $10k.  There is also the model up (032) for just under $13k.  I had big  Krell separates and the 032 integrated offered significant improvement in all areas of SQ including PRAT even though it puts out less than half the power.  IMHO add it to your short list.  Good luck

I too recommend the A40.  This amp is an incredible bargain—lively, muscular sounding, big soundstage, and plenty of “weight” to the sound.  The built in DaC is very good too.  If you are looking to spend more for more power and a touch more authority, the A40’s big brother, the A100 Titan is killer good too.  

Another vote for Pass amps

My vote is Accuphase E-480. Many new models out the E-480 can be had for well under 10k 

Deja Vu audio sells Synthesis and they are all about tube gear with PRAT. You can’t go wrong talking to those folks most likely.