"Unfortunately, eBay is our only outlet for these, as we can't sell them in our shop due the fact that we are in central Scotland where religious divides run deep, and it would damage business if we were seen to be on any particular side of that divide," McMillan said.
He plans to post new items that bid farewell to Pope Benedict and welcome the new pope this week, including new T-shirts and mugs.
"We will have new merchandise for the new pope as soon as he is announced. I pretty much expect we'll do that as soon as photographs are available," McMillan said.
If other famous events are references, such as Prince William and Kate Middleton's wedding and the queen's golden jubilee, McMillan expects "rapid sales quite quickly."
"There might be a small rise in Benedict memorabilia for a short period, and then I expect interest to recede quickly," McMillan said. "Major world events like this are always good for business."