Well Weidmann and Oliva and Harris have been discounted - so I'll have a couple of complete stabs in the dark...
Mike Hunter? (He can do so many
fabulous things with glass - this vase would not be an impossible feat for him.).
Allistair Malcolm? (Again, a man full of surprises and incredible talent.)
But you're in Austria, unlikely to have come across either of these contemporary british makers, particularly in the secondary market.