eBay usually has a pretty good selection of Winnie the Pooh items for cross stitch, though it's easier to find the Disney version than it is to find the Classic Pooh items.

Last year, I did a piece for a friend who decorated her nursery in a Classic Pooh theme. I couldn't find a birth sampler I really liked, so I ended up ordering the pattern called '100 Aker Wood' from England and modifying it to include a border containing the name and relevant birth information. If you're looking for Classic Pooh, you might have a better chance since you live in the UK.

Also, look for a book called 'Storybook Favorites in Cross-Stitch' by Gillian Souter.

Here is a link that might be useful: eBay item