Hi Legsy
While googling glass, by chance I stumbled upon some images of Karl Wiedmann's mid-century designs for Gral Glashütte. They have the dense, mottled polychrome effects of your vase, combined with coloured elongated bubbles. You mention Gral in the title of your post, and I wondered whether it might be worth doing an extensive image search for Wiedmann's designs? A lot of the images I've described were tagged 'Unikat', which implies each was a one-off, albeit a combination of the same ideas and elements.
Just a thought, but I hope it leads somewhere.