Found in a bag of protractors, rulers, circle templates, and a Dietzgen 12152-13.

The thing, neutral Masonite background:

https://i.imgur.com/XAQUt7d.jpg

The thing, on top of the bag it came out of, photographed by a stranger with bear feet:

https://i.imgur.com/3KF13WR.jpg

Here's a shot that shows a stamped mark that reads 9½P1:

https://imgur.com/a/u24OmSh