Yes, you can buy frozen wild alaskan salmon in bags frozen in Tesco. Handy because they’re individually frozen. I buy Monkfisk and Mackeral from a farmers market where the fishmonger gave me reassurance it had been caught in the Irish Sea and not farmed. Prawns, scallop, anchovy & crab too but try small amounts first as test foods. I also eat tinned wild salmon & sardines. Tuna is so mass produced I was avoiding it… tried a fresh steak once and had a severe histadine reaction (can happen when a tuna isn’t caught & handled correctly) so won’t be having that again!