Really depends on how much you intend on using it during any given day. Need to consider: size of memory, the file types it will play, how long it will last on one charge(battery), and ease of use. You can try over one ebay and see what you can find. Do some background checks on different brands 1st though.
uponthis, look, it may sound hypocritical, seeing as my sig is 200kb. but @ 1mb your sig is a bit on the 'wahey too big' side