You can mail a package, up to 8 ounces, to Canada for $10. This includes tracking, but does not include insurance. In fact, insurance is not available for this type of package. You will need a customs form attached to the package. If you print your postage through eBay/PayPal, the cost will be $9.50 and the label that you print will include the customs form.
A one pound Priority International package to Canada runs from $33 to $40, depending on the zone/province. This price includes tracking. $700 insurance costs $10.45. So, the Loes card at $700 will run somewhere between $43 and $51. The packaging is free through the Post office. If you print the label through eBay/PayPal you will save about two bucks and the customs form will be printed for you.
This link will take you to the current Domestic and International pricing from the Post Office.
https://pe.usps.com/text/dmm300/notice123.htm#_c432