[LargeFormat] "new" lens

[philip.lambert]

I just replaced a decent 203mm Ektar f7.7 with an as new 210mm Schneider
Xenar f6.1   (what strange apertures!) in the hope of getting a more
contrasty image. Maybe the definition will be sharper but the Ektar wasn't
bad. I used it as a long focus lens on a 2x3 Graphic, which necessitated
making a tubular extension on a lensboard as the bellows are too short for a
203mm.   I bought the new Xenar because the modern tiny f5.6 150mm Xenar I
bought a couple of years ago is excellent. Certainly the consistent accuracy
of modern Copal shutters is welcome.
What surprised me was that the 210mm Xenar when mounted in place of the
203mm Ektar needed no more extension.
Can anybody tell me where I can find statistics such as back focus in mm on
modern LF lenses?  The data I have is out of date.
As a separate bit of data, the Polaroid Eurynar 135mm and Eurygon 35mm would
seem to be wide field lenses in shutters and possibly useful for technical
cameras. Is anything known about them? A 75mm, 105mm and 127mm Polaroid
Rodenstock and Tomioka/Tominon lenses have worked quite well for me.
Thanks for your time. Philip