If you haven't found an original part by now then this might help.
Just source a thick walled ordinary garden hose. Cut a length equal to the circumference of your spring. Make a split cut along the length of the off-cut piece. Wrap it around the spring base. If it requires it, use some light cable ties to secure the wrap onto the spring base. Reinstall spring.
This is not a critical component and all you are trying to do is avoid the metal to metal abrasion and this approach will do that.