Bad idea trying to beg the buyer to buy insurance.
When I sell on eBay, the shipping price I quote always includes insurance. And I can't tell you the number of people who try and get me to drop it to save them some money, but I always refuse. In fact, after I get one of those I usually add that user to the Prohibited Bidders list because I know they're going to cause trouble.
As a seller, it's your responsibility to get the item into the buyer's hands. The buyer has absolutely no control over how or when the item gets shipped, so the whole "Hey, I shipped it so it's the buyer's problem now" routine doesn't work. eBay and Paypal agree and will yank the money out of your account when the buyer claims he never received it.
The reason I stick people who don't want to pay insurance into the Prohibited Bidders list is these are the crooks who will take your stuff then claim they never received it to get a refund. I've seen it happen many times. At least with insurance, when one of these scumbags tries to cheat you, eventually you'll get your money back from USPS/UPS/whatever.
So remember, shipping insurance is not for the buyer - it protects the seller. And as a seller if you willingly waive the insurance and choose to run naked and unprotected, then don't whine and cry when a dishonest eBay buyer cheats you. Because you were stupid and got what you deserve.