heres post from another forum i hope this helps:

http://www.winchestercollector.org/P...s/F4/F4p1.html

I found this doing a google search for Winchester-Cooey:


The H. W. Cooey Company made guns in Toronto, Canada from 1919. Sometime after WWII the company moved to Cobourg, Ontario, Canada.

In 1961 the Olin Corporation purchased the company and changed the name to Winchester Canada.

Many of the guns after 1961 made and assembled in Cobourg can be confusing; the Cooey single shot shotgun was called the Model 84; later it was modified and the designation was changed to the Model 840.


I would guess it is at least made before 1961 due to the model name being 84 and not 840.

Tom should be able to give you a more specific date with the serial number you provided.