Well eBay will not allow you to add insurance! But, they expect sellers to guarantee that the package will arrive. That is a toughy! So if you want to use media mail for 4 bucks, you cannot add insurance or tracking, so once I give it to USPS there is nothing I can do.
If you want it, we will have to do Priority Shipping. Rates below.
Medium flat rate Priority w $ 100 of insur ance = $15
Large flat rate Priority w $ 200 of insur ance = $20