It appears that they just order generic "small mantis shrimp". That means they get whatever the collectors are gleaning from the reef flats - the most abundant and easiest animals to catch. Typically they supply a mix of Gonodactylus chiragra, G. viridis, Gonodactylaceus glabrous, Haptosquilla stoliurus, and Pseudosquilla ciliata. You pays your money and takes your chances!
Roy