Hi Jenxy,
At ?20.00 for 12.5kg of fondant, you are paying over the odds it seems, I'm sure you can colour your own if necessary. If it is practical to buy a 12.5kg box then you would do well to search this forum and perhaps one on the darker side. Mostly talk is about the availability of a standard 12.5kg box/pack. Frogdogdiver paying ?12.50 is aparently a very good price in NI but not the cheapest price cited as being available in the UK. If my memory serves me correctly, in the last three months prices have been reported ranging from just under ?9.00 (which is exceptionally good) to around ?15 and seem fairly typical, depending where you are. The thing that surprises me just a little is the number of beekeepers that report their baker or bakery supplier as mentioning that they regularly supply a number of beekeepers. Surely a good sign.
Where abouts in the UK are you located? For me, presently it seems that Tamworth 31 miles distant is the most likely outlet, but I haven't actively started looking for a local supplier and will certainly be enquiring in bakers shops about their usage of fondant their suppliers and a price for a box.
Good shopping,
Hombre