Looks to me like the Stroma Bud Vase (design code 4033) in Amethyst (one of the available colours) with additional engraving. The attached image is from the 1992 catalogue, but it shows up already in 1988 - which is my earliest Caithness glassware catalogue, so I cannot say when it was first issued.
Height should be 190 mm if the Stroma Bud Vase. There also seems to be a smaller version of only 170 mm (4022).
The Bud Vase is not mentioned in Mark Hill's book (unless I missed it) but (on page 52) Rose Bowl (4071) and Flower Bowl (4035), which in the catalogues also show up under the Stroma range - with production since the 1970ies.