I agree with John, if I had to hazard a guess I would go for Fratelli Toso too: the canes, (green) ground and shape of dome, all point to FT. I only hesitated because this weight is not perfect (see cane overlap not to mention bubbles) and normally this factory churns out better quality product. Still, bubbles are (more often than not) present in FT paperweights and we can always have a bad day at work!!!
SophieB