I have actually mounted the Agfa Solinar 105mm from my Record III on a 5x4. This is a tessar-type lens and normal for 6x9cm. It illuminates 5x4, but gets soft outside of the intended 6x9 frame. It does not vignette at the corners - you would have to put it on a 5x7 to see the corners really darken. The Synchor-Compur shutter has the close to circular iris mentioned originally, though the lens also mounts in a standard Copal 0 shutter.
I suspect that any lens designed as 'normal' i.e. a focal length close to the diagonal of the format won't work for corner vignetting at the focal lengths you want. You probably need a projection lens of some sort.