Best DAC - Preamp Combo $5 to $10K Budget

DiDiT 212se 

Check out PS Audio Pre & DAC combo.  In that price range and have a trial period I do believe.

Bricasti M3!!

Simaudio 390. 

I would suggest looking into the Chord TT2 and Dave. They are both excellent. If you can stretch a bit I strongly suggest the dCS Bartok. I owned the TT2 and auditioned the Dave and found that the I preferred the Bartok to both of them. It also has a built in network streamer.