Also, take a look at the Matrix Audio element series... I have the element X paired to my McIntosh MA252 and really like the level of detail and expanded sound stage it brings.
+1 for the PS Audio NuWave DAC.
I have the more recent version called the Nuwave DSD Dac - https://www.psaudio.com/products/nuwave-dsd/. A great sounding DAC that is built like a tank.