re: Weathervane 7

I'm a bearing hoarder. Keep thinking that a front car hub wheel bearing and cup would be excellent for something like this. Tapered roller bearing.
Only $5 or so for the cheap ones, about 2" diameter.
A shallow hole to hold the cup, metal washer with a bolt welded on that is just a tad bigger than the rear of the cups ID, then the bolt through the bearing to attach to the mounting post.
The cup could be secured in the hole with small washers overlapping its edges.