Our builders in Australia have been using a service called Reship.com in Portland OR. Basically we ship to them, and they ship to you at a discounted bulk rate. They give you a unique shipping address at their site, kind of like PO Box. Shipping doesn't take long, only a week or so. To date our builders have had great success and no damaged parcels. This shipping option is approximately 1/4 of the cost of shipping directly with conventional shipping (UPS, Fedex or DHL).
The website is Reship.com - you will have to signup with them.
This works well for engine parts, avionics, propellers and smaller airframe kits like the tail kits.
UPS shipping from SPA to Reship is approximately $100 for the tail kit parcels.
The UPS girth limit is 165 and the weight limit is 150 lbs. So the tail kit will ship via UPS, however the fuselage and wings spars will not. These will have to go regular freight.