Although a bit above your price range used, I think the Ayre Qb-9 would provide what you're looking for and might be worth saving your pennies for if none of the lower-cost options pan out. Best of luck.
dac advice
HI my system is Rogue Tempest, appletv for my music it is in lossless,AIFF if I remember,and a pair of Mark&Daniel's Mini's, looking for a dac used or new $500 to $800 approx,considering psaudio dac iii, also easten electric dac,peachtree dac-it,has anyone heard these and what else would you suggest,I am looking for musicallity,smooth analog sound is most important to me, thanks for any imput, Nick