The PN on the box matches with a 47-51 Right side lock assembly from the parts listing. Maybe it was manufactured much later, so could be a NOS lock.
I recall seeing the "COWLES" stamped on my original door locks, but I'd have to go dig them out of the parts pile to confirm that.
Looks like you may have made a good score. Too bad it's not a driver's side lock. Those are the ones that take a beating.


Kevin
1951 Chevy 3100 work truck
Follow this saga in Project Journal
Photos
1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car)
Busting rust since the mid-60's
If you're smart enough to take it apart, you darn well better be smart enough to put it back together.