To the best of my knowledge (which these days may not be as accurate as it used to be), one example of a badge weight I have, which is set on a pedestal stem and foot, came to the market through the former Sweetbriar Gallery with a provenance of "from the Ysart family", but no further details of the provenance were given.
That item, and others that may also have had an "Ysart family" provenance, are useful for comparison, but even then, as Martin has said, it can still be difficult. This is especially true for for examples with an unfinished base. Note that most shown in the Scotland's Glass site have a smooth polished (some concave) base, rather than a remaining pontil mark.
I cannot prove it, but any badge weight which has a large round pontil mark or which is unstable because the "pontil button" causes the weight to wobble would, in my view, fit in Martin's scale at a point below "5".
Note also that in the Scotland's Glass site, Colin Mahoney (author of Masterworks: the paperweights of Paul Ysart) has stated that longwave uv results tie up with what he has recorded as being pre-war Moncrieff. To date, I have been unable to replicate Colin's findings regarding the pre- and post-war split relating to uv reaction. That does not mean I think Colin is wrong, just that my own uv tests on early PY weights have not shown a definitive result.
One other thing ... Salvador Ysart (or someone else at the Ysart Brothers works) [See Derek's post added while I was typing] also made some badge weights. And can we say for certain the Belgium was the only country in mainland Europe where such weights were made? What about the Alsace area of France?
It's almost as tricky as the multitude of "Harlequin" or "Frit and Bubble" weights that are invariably offered as Paul Ysart but which could have been made in various European locations, including Germany.
Hence my current view of "I don't know" for the majority of these weights that crop up so often.