Michael,
The bubbles in my Cenedese piece are made using the same technique as the bubbles in your piece. However, I think your piece is a little more complex than mine. It reminds me of the Stejskal pieces for Skrdlovice, but not with one colours.
I don't see the scratches on the base ruling out Murano as I've got pieces that I'm fairly sure are Murano with similar wear. Ordinarily, I would follow Ivo, but, with a little moral support from the good Dr. Fischer, I'll go with Murano.
David