Best used DAC under $750.


I am currently using the DAC section of my Mac 2500. Would like to have a separate. Also would like xlr outs. Not looking to buy new or spend more than $500-$750. I appreciate your recommendations from your experience. I have owned several separates in the past. Antelope Gold, Wadia 121, AMR 777, April Music ??
dpm2340
A used Benchmark DAC1 HDR would fit in the ~$600 budget and has XLR out. I've had mine for about 10 years, use it as a DAC and preamp and have no complaints.
Three Things to look for:
1. Not over 5 years old
2. A Ladder DAC
3. Tubes
4. Volume control 

Smart to go budget now as these are improving quite quickly.

Keep us posted please. Hurray for #4.
How about a new R2R DAC for under $700.00? DENAFRIPS ARES is an incredible bargain. IMHO
I posted here for DACs I wouldn't even know about. You guys have given me several ideas to investigate. thanks
IF needing USB you will want to use a USB/SPDIF converter with either the aforementioned PS Audio DL III or my suggestion, the Bryston BDA-1.  The going used rate for the PS Audio is $300-350 or for the Bryston BDA-1 is $600-800. I have owned both, the Bryston is somewhat better and has far more inputs. Both have XLR and RCA outputs.