What it reminds me of is the old hard rubber tires ( this looks iron of some sort ) that we used to have on our old wagon as a kid with the hole on the edge to drain out the water.
Could this have been a tire for a wheel barrel or something similar?
I know way out in left field, but it could lead someone in a new direction...
Bought at estate sale out in the barn in West Texas. Paid a couple bucks, can't remember really. Iron, hand forged. Was told it was a flapper valve for a pipeline, without the flapper...