Yeah... I'd never heard of 'em before.
And I just looked again at the photo - with my glasses on I can now clearly see that mark.
What a doof I am to not have looked more carefully before posting.
I took those photos a minute or so after it had arrived today, and I thought 'this doesn't seem right for WF', but only ever having bought 4 9308 weights as gifts I'm not an expert.
It had various bits of paint and crud on the body, and there really is some sticky label-glue-type crap on the base (which doesn't show on the photo) - which I didn't clean it because it came complete with a smashed dish (see attached pic) and after cleaning-up the powdered glass which had spilled when I opened the package I just wanted to file a claim with the eBay seller.
Oh well, such is life.