I do not believe in re tipping. If you want it remanufactured send it back to Shelter. The Clearaudio Essence MC and the Audio Technic AT ART9 are both excellent trackers and solid sonic performers. I have never listened to the Shelter so I can not compare but to get significantly better performers than these you would have to spend 3-4 times as much.
Shelter 501 mkii then what now
I bought a Shelter 501 mk ii around 10 years ago and most folks on Agon then thought it was the best value cartridge of its time. what is the current around thousand dollar cartridge champion