I would beleive that ICON would be the maker, as recent (from a few years' ago that are being "caught up with" now) Nevada Gaming Regs require that the manufacturer's name or logo be on at least one side of the chip.

This is why many similar "re-order" looking chips have been released in the last year or so, mainly from paulson with a smaller inlay and the addition of the little hat & cane logo. Casinos who did these new chips to include makers logo are Hooters, Luxor, Mandalay Bay, Harrahs, O'Sheas, Imperial Palace etc.

Notice in the pic the smaller inlay (but same graphic) and the added logo.