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Please correct me if I misunderstood your two (now consolidated) posts. I assume you reposted because vulgaris was not one of the animals you meant and that you are looking for either a bimaculoides or a briareus.
Bimacs are primarily found in the tide pools of California. Unfortunately, they cannot be collected and sold live so obtaining them as a home aquarist is difficult. They also require a chiller (temps below 72) and is something many aquarist cannot easily provide. They are (as are many coldwater octopuses) longer lived than their warmer water cousins and have been the most successful we have seen for raising hatchlings.
Briareus are from south Florida and can be collected wild. Sourcing them has been more a matter of luck than any common source. Most are captured in crab traps by fishermen who will occasionally offer them to retailers or found in aquaculturesd live rock harvested by licensed collectors. When known, the list of our octopuses at the top of the Octopus Care -> Journals and Photos sub-forum contains the names of the various collectors that have them for sale.
A second warm water alternative would be O. hummelincki. It is the warm water equivalent of the bimac (very similar in looks but is warm water, shorter lived and a small egg species so raising hatchlings are not currently an option). These would be sources similar to O. briareus but may also be imported from Haiti. They are often listed as a Caribbean two spot or Caribbean bimac and are typically sold through on-line stores located in FL.