1970 ladies Bulova - can anyone help

This watch was given to my mother by my father in the early 70's. It still works well and keeps good time although it has never been serviced.

The case back is marked NO (1970) and there are no other markings on the watch body.

The strap is hallmarked 18k white gold bracelet and is also marked "Made in UK". Can anyone help me identify this please.