The GW fantasy line has a couple options in their Tomb King and Vampire Count lines. There are tons of bits in those skelly boxes, enough to make it worthwhile buying the whole box just for the chests. If you only need one or two, I'd suggest asking a local fantasy player, most have the skeleton boxes even if they don't play TK or VC. If there's no local forum, maybe just stop by the local GW on fantasy night? If there is one.
There are lots of other options though, I don't own them so can't recommend.