Unfortunately, no. It has to be an eBay sale.
However, if you need to buy shipping insurance for non-eBay sales (or just for something else you want to ship), you can go to www.u-pic.com and buy it directly. It's pretty affordable, and U-PIC is the same company that provides insurance to Auctiva users (i.e. when you use Auctiva insurance, you are actually buying U-PIC insurance).