I sent an item to a Canadian buyer and it was received by them, positive feedback received from them and even a little ebay message to say they 'love' the item. A few hours later I get another message saying that they have looked at the item more and now think it's a fake (which it is not) and they're saying how could I expect them to accept the item and are having a go at me for being disreputable etc. 

I told them to lodge a dispute with ebay but return postage is up to them and that I will only provide a refund once the item is back here in Australia. (the person says they are 81 years old) How do others deal with this kind of thing?