Hi Malcolm
Looks to me like a 100% genuine Strathearn star. Many Strathearn weights are, IMHO, quite rough and ready, and of modest quality. There are some very neat and attractive ones too, of course: I once bought over 400 Strathearn weights, and the quality varied wildly, even amongst the weights with a Strathearn label.
I don't think there would be any profit to speak of in copying these low end Strathearn weights, so I don't think anyone has done so.
Alan