Best $300 or less Tube Headphone Amp


I have a pair of Sennheiser HD600 cans and I'm looking for a $300 or less tube headphone amp that will work well with them. Thanks!
oregon3
ASL MGhead. I use it with my senn hd600, and it has good synergy.

Also, the high gain grado RA-1 actually has a little more detail but you lose some of the tube qualities.
ASL's MG Head DT OTL, now in MK III version. (MK II and III have separate power supply.) You should be able to find a used MK III, and certainly a MK II, for under $300.
I have the Channel Islands with my 600's and it is an incredible pairing. Just a hair above your budget, but worth it IMO