What camera accepts a 62mm x 75mm x 2mm flat lensboard?

I'm not sure whether this question belongs here or in the Medium Format sub-forum...

A completely flat metal lensboard drilled for Copal 0 having dimensions as in the title has found its way to my home. Based on the short focal length of the lens that came on it I guess it must fit a 6x9 (2-1/4" x 3-1/4") camera, but which one? It's not the right size for the 6x9 Hansa, at least not the one I had, and I'm not familiar with any of the other makes of small-format view cameras.

Thank you for enlightening me.

hmm, its not an old 6x9 linhof--they're 74x82. Its not a Horseman VH/VH-R, they're 80x80. 6x9 Arca Swiss is 110x110. 6x9 Cambo, I forget but its much larger that what you have, so is the Galvin 6x9. Those are the 6x9 cameras I know. I know there are a number of 6x9 press cameras, but I don't know them at all.