This would be an impossible ask for me. My door creaks and now I wonder if I am on the path to an impossible hinge problem.
Where is the place to put grease? And if don't have a working grease gun, will spray grease or spray silicone work?

 

As long as the hinge pins haven't contacted the steel outside the bushings and the bushings haven't moved to expand the holes, you should be able to install new bushings and hinge pins.

As for lubrication, I've used white lithium spray grease to apply it to where the pins contact the bushings.