Just in time for Christmas day.
The Halfords 33pc Variety Battery Pack contains the most commonly used batteries in the UK. The pack contains 20 x AA, 8 x AAA, 2 x C, 2 x D, 1 x 9V alkaline batteries.
Even at the pound shop, you would spend more than this for this many batteries, plus you get a storage box too!
Probably not as good as named brands, but good nevertheless.
Online and in store (check before you travel as the stock checker is a bit random)