That stencil and many other good ones are in this book:
http://www.amazon.co.uk/exec/obidos/ASIN/0954170415/?tag=clarkeology-21
Also, the guy who did it's website is this: http://www.banksy.co.uk/
Andy
Paul Clarke's weblog - I live in A small town, Kent. Wed and father to two, I'm a full stack web engineer, and I do javascript / nodejs, some ruby, other languages ect ect. I like pubs, parkrun, eating, home-automation and other diy jiggery-pokery, history, tree stuff, TV, squirrels, pirates, lego, and TIME TRAVEL.