Many of these "badge weights" are sold as being made by Paul Ysart in the 1930s. But several collectors believe that a lot of them were made in Belgium (and perhaps elsewhere). The problem is that we have no certain way of knowing which really were by Paul Ysart (unless there is provable provenance) and which were by some other maker.
Personally, I suspect ones with a "large pontil mark" are not by Paul Ysart. But when the pontil mark is neither one thing or another, it is hard to decide anything. It's a similar problem with the very many "frit and bubble" weights that get sold with a Paul Ysart "early harlequin" attribution. They are the same sort of weight (bread and butter stuff) but with a bubble motif instead of a badge, and the finishing is is much the same.