Hi Bryn - have to say that I'm also going with Keith's thoughts on date.
glass from seventeen something - as you're suggesting - is recognizable often by shape and form, and this one to me has more of a C20 abstract look to the design - the proportions also make me think nineteen something.
Unfortunately, the inclusions, pontil scar, striations etc. aren't conclusive when it comes to determining age, although you may well be correct in suggesting a Continental origin.
You don't mention wear, which I'm thinking might be considerable if this were well over 200 years old.
Regret I'm very dim when it comes to C18 coloured glass, but books that offer a little info on general shapes and some guidance are..........
'Coloured Glass' - David & Middlemas............. and for a potted overview of Continental material...... Janet Seligman's translation of Gustav Weiss's volume 'the book of Glass'.