Heck, you can't even get sweets for that anymore.
Traditional ATB tread
Classic white rubber construction
reportedly in stock at: Hemel Hempstead, Watford, Borehamwood, Harlow, Peterborough, Galasheilds, Hull, Beverly, Wandsworth, Kilburn. and many more (probably)
In stock - Irvine, Ayr, Kilmarnock and Braehead.