We have Imported Zebra Ottos before, and they are notoriously sensative to water quality. This is usually why you don't see them, as most wholesalers dont mess with fish that have high DOAs. Not to mention the Zebra Ottos are quite expensive, I would say $10/ea is a good deal. We sell ours usually for like $40-50 for a group of 5.. They come in larger then regular Ottos too, like 1-1.5"..
they kinda do look like flying foxes aswell mind (not the zebra variety). i prefer the otos though, got about 6, they make a nice little grouping fish, and dont devour plants like some plecos do. mine seem to have maxed out at an inch.