Thanks for all the helpful advice and input, it was much appreciated. I got eBay to ring me and explained the situation and they allowed me to refund the buyer minus the postage and also organized for the eBay fees to be reimbursed to me. 

So quite a positive outcome really. The buyer may end up still buying the items but even if not, at least it was handled with some integrity and the outcome hopefully is ok for both of us. Thanks again.