Not sure what you are looking for sound wise, but if you want to come close to the sound of analog with your digital set-up, then a non-os DAC is the way to go IMO. You can get one in your range very easily, with an excellent digital cable to boot. Check out the Audio Note and Sakura Systems (47 Lab) websites for information on non-os design. Right now there is a new 47 Lab Shigaraki here for $1000. I have the Audio Mirror DAC that I purchased here on Audiogon new for $500. Then I sent it to TRL for their mods ($550). It is an incredible sounding DAC for the money (see my review here).
Good luck with your search.
Good luck with your search.