R to r dacs

Now that Cees Ruetenburg is back at the helm at Metrum Acoustics, I would consider the Jade R2R DAC with their Ambre streamer. 

Those fit your budget and the Ambre streamer can come with a Roon SD card or a Volumio SD card installed or purchase both.

Im running their Pavane DAC with Ambre streamer w/ Roon

That was a great deal on la voce dac.  I saw a l scala used at 5k and waited to see cash flow receipts today and make an offer.  Gone

Extremely happy Pontus user here.
You might want to consider an Antipodes streamer/server. Excellent build and sound quality.

What really stands out for me with these 2 products is the terrific after sale service should you need it.

Good luck with your decision.

With your budget I'd go with Soekris 2541 Dac

Another Denafrips fan here. I started with the Terminator with upgraded DSP board, then added the Gaia DDC. The DAC by itself was excellent, but adding the Gaia with an i2s connection to the DAC was a VERY meaningful improvement. I've since traded my Terminator for a Terminator Plus which takes it up another notch. 

I think the Pontus II would be a great option, particularly since you can get a nice performance boost down the road by adding an Iris or Gaia DDC.