What a wonderful and extremely rare addition to your collection Nick, congratulations!!!
Eventhough i am no Bing expert by far, i would have to slightly disagree with your dating of the 10/2102, and lean stronger towards other sources, which dates these between late 1920s and early 1930īs.
Here it is, cropped from the 1930 catalogue, so at the very least, it would not be gone by 1929:
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