I think the eBay seller has done the right thing by adding "?" to the Perthshire attribution in the title.
In my web pages, I show
a neatly set spoke weight which I classed as Strathearn but with reservations because of the tidiness and the 1-1-2-2 cane pattern.
Although I cannot locate the email right now, a collector in Europe sent me a photo of an extremely similar weight to mine, with the same pattern and much the same quality of canes etc. But his had a Perthshire Paperweights label. (Ok, in theory, the label may have been added to a Strathearn weight in error, after falling off the correct item, or it could even have been added, at any time before the current owner received it, as a deliberate attempt to mislead.)
But assuming the label was added at the time of making the weight, it confirms use of canes that, to me, look very much like Strathearn but in a Perthshire weight. I have always felt (even without absolute proof) that many of the early Perthshire weights would have been made with Strathearn canes (or even early Vasart [and maybe even earlier Ysart] canes, too!).
For the eBay one my first thought was "unsigned Perthshire", mainly because of its tidiness set off by those very neat and straight filigree twists - a feature not often seen with Stathearn twists when set in the weight.