I second that, I have picked up a few gold and silver bargains on eBay over the last couple of years with only 1 gold and 1 silver coin that didn't pass the XRF test at my local bullion dealer and both times I got a refund.
The silver was the CuNi version (a 60's Greek coin) and I had to go through the dispute process as they refused to answer my refund request (I got to keep it as well since I couldn't return it without an address) and the gold coin (a modern Australian 1/4oz) was refunded after a week, although begrudgingly and a day short of being able to involve eBay (that one was returned)