I have never seen or heard of another yarn holder of this design, but I have now found an ad for it, that appeared in Good Needlework magazine in August 1935.
The ad says:
With "SUSIE" you Knit Quicker — keep the wool clean — you can knit in comfort whilst travelling. The wool follows the needles making tangling impossible. Post Coupon now for return post delivery, enclosing 8d. P.O. [postal order], or stamps.As you can see from the drawing, it has a bangle to go round your wrist, and the V-shaped piece of wire with the two little balls on the ends goes through the middle of the ball of wool - as I had already worked out, more or less.
The fact that I have never seen another like it, nor any other ads, suggests that it didn't catch on. I had assumed, when I first saw the example in the Guild collection, that it was designed for use with ready-wound wool - it's easy then to push the wooden balls through the hole in the middle. But in the 1930s, most knitting yarn was sold in skeins, and to use the 'Susie' you would have to wind the yarn around a section of broom handle, or a nostepinne, or something similar, to get the same effect. (I don't think mechanical wool winders were available then.) If you were used to winding wool into quite tight spherical balls (which is what I do when I'm winding by hand), it wouldn't work. Or you might think, from the drawing in the ad, that you would have to wind the wool directly onto the yarn holder, which looks really awkward. I suspect you would only buy one if you saw a demonstration, or on personal recommendation from someone you knew. If it had been sold through yarn shops and not by mail order, it might have done better. It's a pity - it's an ingenious design and deserved to succeed. It might be more successful now, when most commercial yarn is sold ready-wound.
The company that sold it is named in the ad as Tormidor Ltd., with an address at 5 Rampayne Street, London S.W.1. I can't find out anything about Tormidor - any further information gratefully received.