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 1930´s.
Here it is, cropped from the 1930 catalogue, so at the very least, it would not be gone by 1929:
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