Holland & Barrett don't sell vegan cheese online (although they do have a vegan cheese sauce mix) but it could be worth checking for chilled food cabinets in their stores.
>>>I believe all the big supermarkets (including the Co-Op) sell vegan cheese
Most supermarkets will probably stock vegetarian cheeses (i.e. made with a rennet substitute) but I can't recall ever seeing any vegan cheeses (i.e. made without milk).