Matrix Audio... the element I that i had was utterly superb as both a DAC and a headphone amp, and i'm still convinced there was no need for me to even have upgraded to anything else. It was painfully close to a DCS rossini to these ears, and if id left the room and came back in, i wouldn't have been able to tell you which one was playing.
Its a classic "good is good enough" level of DAC that gets on with its job.
The new one has a better power supply and doesn't need an external power brick, so I'd recommend the new one, which you may be able to find within your budget I'd think.