I doubt that Andy Muzi has the records that go back far.

I purchased my bike in the spring of 1980. My bike frame is unusual. It is made for small people. I am 5' 2" and have a very hard time large or average size frames. Not a lot of people would have been interested in that tiny frame.

The lug on the front stem is a single lug, not the usual two lugs.

Can I prove that it was built in 1979? No.

I believe that it was built sometime in 1979, and after export to the US, and then to Madison Wi, it was not an immediate seller and was in the shop in the spring of 1980, when I was looking for a bike.