Weaver b4 scope with N3 side mount years?

[Mr.4x4]

I have an old winchester model 69a with no year on it. It looks like the weaver b4 scope and n3 side mount were put on when the rifle was new as the bluing is still under the mount and the scopes paint is still under the rings.

I'm trying to put a time frame of when the rifle was made and wondering when weaver made the b4 scope with N3 side mount. The whole rifle has next to no bluing but has a nice antique patina all over as well as the scope.

Thanks !

 

[kamlooky]

Lots of info on rimfire central.
Look at the trigger.
If it is smooth it's my understanding that would make it pre war.
Serrated make it post war.