We are about to get a wall rebuilt and it would be great if we could have gate posts that where in the same style as the rest of the road. As I don't know the same of the style I have nothing to start with on google.
I don't know where you would buy it but it would be really easy to pour it. Just build a box the size you want the post to be. You could put any kind of medallion or symbol at the top of it. Pour the appropriate amount of concrete in (probably 2 bags?) Then run a vibrating sander over the outside of the form or box in order to get any air bubbles out. Let it dry and pull the form off.