Island hobbies have it at cheaper rates than probuild, cos VAT is not included in the prices. I have ordered a fair few props(14x5N and 16x4W to name a few) from them already by post, and postage has been very prompt and reliable also. They have got quite an extensive range of props to. On www.flycapiche.co.uk there is an excellent propeller list under the how to order section, with prices.
Hope this was of some help