On Friday, January 19, 2018 at 10:44:35 AM UTC-6, wrote:
.. someone suggested it was a sex toy .. ouch !

https://imgur.com/a/67YlT

John T.

Might be close to a sexy toy, depending on your leanings.

Pinterest has a similar pic of the sprocket, states it's related to a dairy farm tool. https://www.pinterest.com/pin/496592296384607638

I had Googled "antique farm sprocket tool".

Another Pinterest image, states it's a cistern pump sprocket, pulley.
https://www.pinterest.com/pin/426153183473852990/

Another cistern sprocket: https://picclick.com/Antique-Vintage...060942778.html

Sonny