Help with a Victor #50 portable

[gramophoneshane]

I wonder if the back rubber flange has something to do with it?
Perhaps if the machine was stored on it's side for 20 or 30 yrs, the brass sleeve inside the rubber may have been thrown out of alignment as the rubber hardened.
At any rate, I'd be taking another reproducer I knew to sit correctly along, to slip on the arm to check if the problem lies in the reproducer or the tonearm.