The lighting in your pics make it almost impossible to see the numbers on the movement and back of case.
I did make out that it was a 1001 movement. However, if you could post the numbers in the case back as well as the serial number on the movement (at the bottom of the movement photo. that would help.
It looks like the first 2 digits of the number (??4 digits) in the case are 66 or 65 or 68 and that would be the reference number.
Vacheronm made a series of watches about that size with the 1001 movement, two are Ref. 4667 and 6484. both are from the 1960's
This article by Kent (KBS) may be helpful: http://www.thehourlounge.com/en/vacheron-constantin-discussions/retailer...
But if you could send Alex, our moderator the movement and case numbers, I'm sure he could help.
Thanks a lot for your help.
I guess you are right. I will check the digits (I need to ask someone to open the case because I'm afraid to damage it) .
Kent´s article is also very informative
I already checked. The ref is 6399.
I found one just like mine
Thank you and best regards