This is not intended to be an authenticity check, it's just a first rough guess.
Made and sold in early to
mid 1970's, definitely not late 1960's - my guess: 1975.
For the ref, a difficult to answer question - my best guess, a follower or derivative of ref 2040, but there are many similar looking case designs at that time.
The Vacheron Constantin automatic movement is probably a K1121, with Geneva Hallmark, 36 jewels, segment 21K gold rotor. It is based on a JLC ébauche, but refined and regulated to the much higher standards of Vacheron Constantin - the Haute Horlogerie Maison standards, not the much more basic JLC standards of higher volume manufacturing.
The movement is perceived as the most collectible automatic movements of that time, the stuff the aficionado is recommended to look for.
For further readings about
the K1120 movement check: Link
The structured / textured dial is from the second modern revival of texture style's in the 1970's.
This watch was originally
most probably not accompanied by a gold bracelet. At that time you
could observe the integrated gold bracelet very often (what gives an impressive wrist appearance).
The recommendation for the aficionado: