The one problem with a private sale is that you have to have a good idea of what the true value of the weight is. This is fine for an object where the value can be ascertained by comparison, but for this one? It's really a question of how much the purchaser wants the weight. There are probably a number of whitefriar collectors who havent got one of these initial weights and would really want one. As Roy has said, he has one - as I have, and both of us would quite happily have another but would we pay the same as if we didnt have one?
It's the same for Whitefriar Butterfly owl and bee weights. I havent got one and I want one, but too many other people do and so they are always out of my price range. Or, the square blocks with thermometer and star canes (by the way, I have a spare one of these).
The one thing with ebay is that it is likely to reach the widest audience and find its value.