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What you are looking for is Octopus joubini. There seem to be fewer species of octopus being sold in the US this year than in previous years. Perhaps the availability of tank-bred bimacs has made some local fish stores reluctant to carry other species. I don't know where you could find this species right now.
Everyone: we have a lot of requests for pygmy octos such as O. joubini. Also larger octos such as O. vulgaris. Please let us know if you see these for sale.
Yes, TBSaltwater has two species of octopus on its order form - but one person called them this week, and they hadn't had a vulgaris for a long time. The site that says they will catch them for you hasn't been updated in a while.
And yes, everyone agrees they have wonderful live rock! But not cheap!