Is the eye at an angle?
In my experience, this is one of the most difficult hammers to find. I found one over 25 years ago, and it's the only one I've found at tool swaps or flea markets. It's pretty much the jewel of my blacksmith hammers. As a blade smith hammer, it is used to pack the steel with fairly light taps. It doesn't need a hefty handle.
These were also used in manufacturing the really big old circular saw blades. If you have, or can find, a copy of volume 1 of the older Audel's Carpenters and Builders Guide (the editions published between 1929 and 1947) there's a photograph on page 190 of one of these hammers being used at the Simmonds factory in the production of what looks to be a 5 foot diameter saw blade. The part of the process is called "knocking down" in which the teeth are knocked down or straightened after they have been cut.
"The first operation in the manufacture of a circular saw is the drilling of the center hole. After this the following operations are performed: Toothing, knocking down, hardening, tempering, smithing, stamping, grinding, polishing, etching, filling, and finally, inspecting..." (pg 190-191)
