I would hazard a guess and say that they are the same thing as what coin collectors use. You could probably Google for "coin collecting supplies" and come up with a bunch of them. Or maybe peruse that chip collector's club website for info: http://www.ccgtcc.com/
I'd suggest you get $20 (double eagle) sized holders, they are probably the closest fit. Check out www.coinworld.com and you should be able to find some vendors there.
Air-Tite chip holders. You can get the types with foam around the edges or exactly the same size as the chips. Personally I don't use them, but I know they work well.
you can use the coin holders since its foam that holds the chip in place inside the holder, it will fit snuggly. I bought mines locally from a coin&stamp shop.