anywhere in uk where they sell these
 

pretty much any shop that sells nuts and bolts for a fraction of the cost of those kits.

your paying through the nose for some1 in the US who has bothered to sort out what bolts are used in the engine bay...

take a weekend, ID what bolts you want to make nice.
and ID what length they are and thread and pop into your local ironmongers

should cost you about a tenner tops..

These kits are a rip off IMO. Pop down to your local tool dealer and ask what they cost, you'll be shocked.
I bought a huge bag of 10mm and 12mm S/S nuts and bolts for less than a fiver.

PM ironbridge on here, he does a lovely set with washers for a lot cheaper

If you were on the group buy they're cheaper. That's who's selling them in the Ebay link. ;)

www.tastynuts.com known as probolt