Steffan, I don't know if your £55 price includes VAT and p&p but I can get the price down to £50 (VAT included) + £8 postage on ebay (item no. 230184855156) or you can get one for £40 +VAT and P&p from classsictyres.com (page no.5 on the motorcycle tyres pages) which I think is still going to cost you around £55 anyway. I can't seem to get the price any lower mate.
Bill