I think because they are not very common. 1930s Coleman 223W Your photos should also be in the reference library I think
That's one I've not heard about. Must had been a special unit. The collar and nameplate don't look like what you'd likely see on most other Coleman lanterns.
Welcome from Queensland Australia. What a beauty the 223W is ...... I’ve not seen one of these before, thank you for sharing. Cheers Pete