The extra bubble and base suggest to me it is Belgian. Although Paul Ysart used a similar design, I believe that Salvador and Paul he got the idea for these (and fountain/spider weights, and cap badge weights, and sulphide weights) from the time that they spent in Paris before the First World War. There were (and still are) plenty of these designs around that were made in Belgian (and other northern European) glass factories from the late 19th C onwards.
I have attached images of a 5 bubble 'canopy' version, which I believe is Belgian.
I feel that Paul gets too many cap badge weights and slightly unusual harlequin and spider weights attributed to him: he made quite a lot of these designs, but only a modest proportion of all those in circulation!