Here are a couple of addenda, without pictures yet.

Voigtlaender 9x12 holders (no identifying number; I suspect all Voigtlaenders are the same): width 97 mm, length 147 mm, locating lip 7 mm (measured at the edge of the holder). I can personally confirm that these fit a Voigtlaender Bergheil and Avus, a Nagel Fornidar 30, and a Photo-Porst house-brand camera that I think was made by Orionwerk.

Kodak 9x12 film/plate holder (no model number; they say "Patent U.S.A. 1,933,823"): width 97 mm, length 148 mm, locating lip 6 mm (at edge). Double flange with the groove in between (I'll post a picture); they fit the same cameras as above.

-NT