You've been doing the most cost effective thing. There are no parts distributors in the UK, they are only resellers, so they buy from the U.S, pay shipping, customs etc. then add their margin making it more expensive to buy. Best thing is to get a good list together and buy at once to make the most out of shipping. Alternatively it's possible to get stuff over in a container from places like STS imports. This way you can take advantage of free shipping in the U.S to the docks, then shipping is cheaper too as your stuff is in a container which is being shipped at a fixed rate. This is good for larger parts like body panels but also good for lots of small heavy bits i.e. rotors.
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