Doesn't Ebay have their policy that you are 100% protected as a buyer? If you pay and don't receive your item, they guarantee your money and directly pay you back.
I'd contact Ebay directly first, before PP. They'll try to get in touch with the seller as well.
Also, what's the sellers Ebay rating? I "try" to only deal with sellers with excellent reputations. Sellers who've been selling for at least a year.
Good luck and I hope it works out.