Rockwell 11-280 Radial Drill Press

...

And which part would that be, specifically?

More than likely your only luck will be to find a parts machine somewhere or fabricate something yourself. Rockwell is pretty dated by now; somewhere in the 70s/early-80s iirc.

The OWWM entry also doesn't show a rear belt guard if that's what you think you're missing...

There was one in a shop I used to work in some, but it's been so long ago I don't recall for sure but back then we would have probably tossed it for being in the way during speed changes, anyway... :)

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