+1 @soix -- Agree on not underspending. If you buy used you can re-sell for around the same price. A bit of hassle for a lot of learning. I'd get the Denafrips Pontus and live with it for a while. Just my two cents. (I don't own Denafrips, by the way, but have heard them; they're quite nice.) There's a Venus, too.
In case you are interested in spending a bit more, these seem like real standouts:
Weiss DAC 204 -- I'd offer $2500 and see what happens. These are very very well built and reviewed. There's one lower down the line, too. Perhaps something to bargain for.
Some really praise the Sonnet Morpheus, too. Here.