Is the spherical end a bearing material? Meaning will it offer lubrication and not gall the motor shaft?
I would have thought a oilite/bronze bearing material would have been the correct solution for this?
The original looks like a soft graphited plastic material.
Perhaps one of these?
http://www.spboilles.com/product/Electric-Motor-Spherical-Bronze-Oil-Sintered-Bushing.html
http://www.lm-tarbell.com/sphericals.htm
I would hate to see you have to take the whole mess apart again as a result of having the motor shaft seize on the bearing.
This isn’t something I know much about so your greater knowledge likely supersedes mine.