Many thanks for the reactions. I sent an email to his PayPal-linked email address yesterday and got an answer from somebody else writing on his behalf this morning. She's saying that the seller had to travel unexpectedly and was not reachable by phone or email, but that he is a reputable eBayer and will no doubt honour his commitment. So let's hope for the best. In the meanwhile i have launched a dispute with PayPal to make sure that I still have the opportunity to get back my funds if things don't go as I hope they will. A dispute is not a claim yet but merely flagging to the seller that something is going wrong.