Panerai Compass identification help

[23Zen]

Just acquired mystery compass. I have take it form a guy who didn't now to much about it. And I need some more info. Compass in on the way to me.
What we know till now. 
As Seller told me it is form around 1970. From his knowledge is Dino Zei 70'es Panerai prototype . But I am not so sure. Have bronze /brass buckle w with GPF but see this GPF has not round letter design than I don't know is gen or rep but for sure very nice patina at all.
All comppas I have seen till now was without this kinds of lugs and stright strap. Here is triangular strap . 
So for sure interesting but still don't know what I will have 
So any information , idea will be appreciated. So let this game start .....