I'm assuming you're looking for a reasonably affordable playable set of chips.
HoldemPokerChips.com sells a coin-centred chip by Matsui ("Murphy's Card Room"). The only others I know of are the cheapy "Jackpot Casino" chips (ABS plastic around the outside) and a WSOP rip-off that's similar or worse quality.
If you want something more "impressive", Bud Jones (BJ) makes coin-inlayed casino chips. There are probably several members with playable sets of retired BJ's... but they'll likely cost $2/chip or more!