This is the US equivalent of the Euryscop. It's a gorgeous lens in beautiful shape.
Focal length is 18.5" f6, and as noted on the lens, it is ULF, covers 15X12 inches.
Where this really shines is as a portrait lens on 8X10. It can go in the field. My 6X6 lens boards on the Kodak 2D can just manage it. It's heavy though.
I think it's worth $485 + shipping. Correct original flange is included.