We aren't 3rd world you know, we DO have 2 manufacturers of B&W paper after all, unlike the american continent :-)

More seriously bigger Jessops are ok, stock levels are usually quite low however, I have to order 120 from my local Jessops, normally takes a couple of day, but there are far better dealers.

Should be a Calumet up north east, London you'll have no problems loads of Pro dealers.