No Code, sorry dude. Probably not worth fixing. If you want a Becker, find a 780 model that uses the code so you can just write it on the case and on a card in your records for this event. I did for the one in my SDL.
612 was '85 and down until about '80
754 was 1986-87
780 was 1988-89
1480 for 1990 only
1432 from 1991 to ?? I'm guessing '94.