Search:

Martin definitely made Mandos for Wurlitzer c1923... and they definitely have a Martin stamp as well.
This has been confirmed by Martin historian Greg Hutton, and I have seen one!

Wow, what a pretty instrument! That's some very nice rosewood.
How does it sound and play?

Yeah, the only ones I saw online with vaguely similar style seemed to be German.
The headstock style...

yeah, I'm convinced... but I'll let you know for sure!

Thanks!
I meant to include this pic from the auction too. Either, it'll arrive next week.
I asked them to measure it's length, but shutdown for weekend!
Either way, I'll enjoy when it arrives.
...

Just paid $84USD for this at an auction in Sydney! (hence my first post)

I hope it works....
any clues as to what it is,
my guess from the dimensions in these pics, using the little stickers...