Used DACs for sale - help me choose

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.

If you can stretch budget to buy a new Gustard R26 or look for a used one possibly within budget, you will be happy for a very long time. There was a sale recently that dropped the price down to $1,500. No longer active last I checked. 

Also when it comes to R26, there are ways you can improve it even further once you're ready. Just make sure you like the R2R sound, and the R26 is not your average R2R.