Used DACs for sale - help me choose

A used Ayre Codex would be my choice. Under $1K used, nowadays.

B

I honestly don’t know what to recommend you that’s under $1k that is high-performance. the MHDT Orchid dac and Musical Paradise D2 dac are high performance but slightly out of budget.

Highly recommend people to STAY AWAY from Topping D90SE dac. Very homogenous boring sound.

I own the Musician Pegasus R2R NOS DAC that is excellent and you can get it used for $800 below.  Plus, you can add something like a Pegasus Pisces or Denafrips Iris DDC and take advantage of the Pegasus’ i2S input that upgrades its performance significantly over SPDIF.  I bought a used Iris and was surprised at the increase in performance, so a good future upgrade to look forward to.

https://www.usaudiomart.com/details/649974362-musician-pegasus-r2r-dac/

If you’d prefer Bel Canto I had this DAC 3.0 VBS in my system on demo years ago and it’s also excellent, especially with the VBS power supply.  Here’s one also in your price range…

https://www.usaudiomart.com/details/649954973-bel-canto-dac3-vbs1/

I had them in my system too far apart to make any meaningful comparisons but would put them both on the same level and doubt you’d be disappointed with either.  Hope this helps, and best of luck. 
 

Go for the Denafrips Aries II new or used.