I got this at the local market today. It's a Nivada Electronic Antarctic, with a ESA 9150 movement. As far as I can understand due to the movement, the waterproof on the back and the serial this could be from 1968...anyone agree? It's rather large and takes a 20mm strap which I need to get. The seller was quite insistent in it being an automatic, but he couldn't get it to work..