I was gonna be a real Smart A$$ and just say "In and around Papua New Guinea.."
But i wont.....
lol.
Other than being really lucky and finding a captive breeder with young ones, I haven't seen them imported in a very long time. That and I've heard that the few, if there were more than just the One, collectors that were finding them are no longer in PNG. Could be fact or fiction. I tend to believe it because I've seen more rarer sharks recently than the Halstromi eppies.
Which is a shame, because of all the carpet sharks in the trade, the Papuan Eppie is probably the shark that is most appropriate for captivity.