First of all, this isn't a Cort, although there is a Cort with a similar body shape & neckthrough build, from the same era. Corts were built by Cor-Tek in Korea, but these guitars are most definitely Japanese.
These have been a big talking point on the
www.matsumoku.org board - the same guitars appear with numerous different brands, some well-known (Fernandes), some less so, and their specific factory of origin is still unconfirmed.
Here are a couple of the posts with some interesting info, pics & links:
http://www.matsumoku.org/ggboard/viewto ... =18&t=4477
http://www.matsumoku.org/ggboard/viewto ... =19&t=4667
If you search the Mat board for "Asama" you'll find more - including the curious fact that the name translates to English as "Big Bottom".
Jon.