If I was going over there, I'd want some Full Virginia Flake if it was readily available.
There are a few pouches that I'd also be interested in picking up:
-St. Bruno Flake
-Mick McQuaid Plug
-Player's Navy Flake
Of course I would keep my eyes peeled for other notable brands but those are some I can think of off the top of my head. (They may not be to your tastes, however, so it doesn't hurt to read the reviews first)
I don't know anything about availability in the UK, either, so even the last three could be hard to find for all I know. They are supposedly OTCs but I've heard it is getting increasingly difficult to source such blends.