Eddie51, I'm by no means an expert on eBay permitted sales and it may well be acceptable to buy and sell mercury on eBay. However, this was not the issue. The point I was making was that purchases and sales of mercury along with many chemicals are very likely nowadays to come to the attention of the appropriate authorities.
Whilst bona fide organisations have nothing to fear, sales and purchase via unconventional routes are often subject to scrutiny. Mercury has serious potential in the wrong hands.
I've had a quick look on eBay this evening and cannot find any listings for mercury or its compounds. I appreciate that you sold a quantity there, but I do wonder if sales and purchases remain permissible right now.