Either mislabled or mis-made, it isn't correct for the application that it's labeled for.
My dad wanted the same part for his SM, and went to a somewhat local IH only place. They brought out a new Almost &Incorrect one sealed in the plastic pakage. The situation was the same you're experiencing. They told him to just have the keyway recut to match the old one. For 20 bucks less than they wanted for the wrong part (not counting what the cost of recutting the misplaced keyway would have cost), he had a machine shop make him a shaft.
The new shaft from would have never allowed the brake linkages to function and/or adjust correctly on dad's tractor without reworking the keyway. I'm pretty sure the length was a little off, too. That shaft probably fits something. It wouldn't work on dad's Stage II Super M.
Find a local machine shop. They can either build yours up and turn it back down, or just make you a new one. They aren't exceptionally hard or any special steel. You probably could get it heat treated if you really wanted to, but the last one survived roughly 60 years.
This post was edited by AG in IN at 06:44:58 02/22/13.
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