Old wooden 3 hole bowling ball

This is a smallish sized ,roughly 7 inch, and heavy 10 -12 lb wooden bowlin ball with no makers marks I can see. Seems to be in good condition with no cracks or chips. I found this at a garage sale and seller did not know what it was. 

There are three holes in the ball but not like modern balls, these are all in one line and the two end holes are what looks to be a single bore made threw the center although one is sized slightly tighter than the other. 

Wondering what the estiimate on value could be