The shape is very reminiscent of a design by Metelak for Harrach, but the example I'm looking at on p. 73 of 'Sklo' (Mark Hill) is not bubbled. Other shapes he designed have much larger, elliptical bubbles than your example, some having mica in the bubbles. The book isn't definitive, and I've only recently started to learn about this area, so someone else here might have a better idea.