It looks a tad short to be a hitching post to me, so I wouldn't make it a forgone conclusion that this is livery themed. I'm not saying it's not by any means, but wouldn't having a horse on it be more appropriate? It's hard to tell if the gentleman is wearing a shirt or a breastplate. It "looks" like a breastplate, but I would expect him to be wearing a helmet as well, and that doesn't look like any kind of helmet I've ever seen. It looks also like maybe some buttons on his shirt (if a shirt it is)? This is a very confusing piece
. I still think it might be a wax stamp. It's size, thickness, shape etc are Consistent with that hypothesis. Some wax stamps are made as one piece with a short metal handle, and sometimes with a wood or antler handle, or soldered to a separate piece of metal. I dunno, that's the best guess that I have.
I would have been very stoked to find something like this. The only thing I ever found of any interest with my metal detector was an arrowhead next to a piece of rusty trash!