I like my new Shanling CD-S100, but it's probably too far under your budget limit for you to consider. $600 is about what it costs new. Still, I'd put it up against several of the suggestions here, since it's really an amazing value.
However I would like to say that IMHO you are spending your main budget too far downstream. As UHF mag said, put a $3000 pair of speakers on a boombox, and you've got... what ? But put a $3000 source on a boombox, and you've got something to listen to ( while you save to replace the boombox ). In other words, a great source is listenable through anything. Really. But high class speakers will only reveal defects in your source more painfully clearly.
However I would like to say that IMHO you are spending your main budget too far downstream. As UHF mag said, put a $3000 pair of speakers on a boombox, and you've got... what ? But put a $3000 source on a boombox, and you've got something to listen to ( while you save to replace the boombox ). In other words, a great source is listenable through anything. Really. But high class speakers will only reveal defects in your source more painfully clearly.