Sugarpaste and fondant are NOT the same thing in the UK - the 'fondant' you are looking at is the stuff that makes fondant fancies (think Mr Kipling) - a soft, smooth, spreadable covering.
If you're wanting sugarpaste to roll out and use to cover celebration cakes then you need to look at Bako's sugarpaste - it comes in 5kg and 10kg for £12.39 and £23.64 respectively, I have used it before and it is good, nice to work with and gives a good finish.
The fact that what we know as sugarpaste in UK is known as fondant in USA is very confusing when UK fondant is a different product entirely.