the trekstor vibez is a great player that plays FLACs
http://www.amazon.com/TrekStor-vibez-Player-Black-Silver/dp/B000KDZR5Uit comes in either 8gb or 12gb, but I think* it's possible to open it up, take out the microdrive, and put in a flash card. you could put in a 32 gb flash card, reload the firmware, and be good to go with much more space.
the vibez itself is ~$130 + $65 for a 32gb CF card (from newegg:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820211244) and you're in for about $200.
* I say I
think it's possible because I seem to recall reading about doing this on the internet somewhere. I've been meaning to do it with mine (to get more space & it should increase battery life - which I am already very pleased with. I think I get 8-9 hours on a full charge), but I haven't yet done this, so you might want to do more research before making your choice.