Just read this from PP:-
Seller Protection Programme
Section 11.1 is amended to clarify the scope of the Seller Protection Programme. The amended section 11.1 reads as follows:
“11.1 What is PayPal seller protection?
If you are the recipient of a payment made by a customer ("Payment Recipient"), we may reimburse you an amount for Claims, Chargebacks, or Reversals made against you based on the following reasons:
a. A Chargeback or Reversal was issued against you for the reason of an “Unauthorised Payment”; or
b. A Chargeback or Claim was issued against you for the reason of “Not Received”,
where PayPal receives from you proof that the item was posted or delivered in accordance with the requirements set forth below, subject to the further provisions of this section 11 (including, without limitation, the Eligibility Requirements at section 11.6)."
So if someone doesn't receive the goods and the buyer does a PP claim and wins, if you have proof of postage, or proof of delivery, PP will "reimburse you an amount" for the buyers chargeback.
Don't know the section 11 it's referring to, don't know the details on the amount they'll reimburse you for? I can't see it being the full amount, if it was PP would be offering it's own postal insurance service for free - and there's no chance they're doing something for nothing!!
A little glimmer of hope though.