looking for one and i phoned someone up asking and I wasn't aware they are seasonal. that being said though we have a lot of fish and every time we got to get some more if some die etc. I never see any.
Hi octo_dude and welcome to the site! I cannot find a place in the UK that often. has octopuses in stock.
We are getting more requests from would-be octo keepers in the UK, so maybe Fish stores will eventually carry more of them.
I believe most UK members have located a nearby aquarium store buys from wholesalers (most do). Asking them to order an octopus is viable but what you will eventually get could be challenging. If you find a store that will order for you, be sure you tell them you do not want a blue ring.
Tropic Marine Centre (TMC) get the more comon ones in occasionally. Most Fish shops in the UK deal with them and then its a case of finding a friendly local fish shop who will watching the list's weekly and call you when one pops up. They usually just refer to all of them with a generic trade name of brown octopus and you just take pot luck.
Also abyss aquatics (online) may get them in.