David,
Additionally you can get caught for import tax. This is an amount between 3 and 9% based on the classification of the goods. This tax can be payable if the order value exceeds £135. Pen parts should get the lower charge of 3% but you are at the whim of the customs assessor. This tax is applied to the value of the goods and the vat then charged on the purchase and import tax value.
Jim from pencrafts.co.uk is a psi dealer and is based in Glasgow. Depending on what you are after you might be better off asking him to get them in for you as he will be paying the taxes as well but at a lower rate. The psi postage charges are very high but I only tried to buy direct from them once so they might have changed. The staff at psi are about as much helpful as an phillipines call centre and fail to acknowledge that the world is round and that there are bits of the world that aren't called America.
