Either GPS+ or the Autopilot+ starter kit now available for £15 plus shipping. For that you will get two laser-cut acrylic panels (front and rear) and the construction manual (by email).
Shipping for up to to panels (500g) to the UK is £3.80 by First Class. Shipping to USA (and many other international locations) is £12.95 (up to 500g) or £14.95 (up to 750g). International shipping is Royal Mail International Tracked and Signed (5-7 business days).
The only way to order is to send me a private message here and payment will be by PayPal (or cash, I suppose).