Its serial number places it as having been built in early 1965. As you can see from the pictures, most of the lacquer is gone, there are minor dents throughout, and there's evidence of solder work in a couple places.
It may have light signs of use, as shown in the images. This horn shows signs of use. It looks and works great. See photos for more details. Low Pricing, Flexibility. This is very rare, but is a possibility.