The Frustration
If you are reading about this, like myself, you must have had a rough time searching for answers about this exact problem. If you are one who've taken this to an auto repair shop to see if they have a viable solution, more than likely you spend $$$ on an aftermarket knob that didn't work very well or the darn shifter ended up breaking again. The reason behind it is the shift level in itself. Most auto repair shop will not have the information needed or care enough to take the time and fix this the right way. So if you are reading this, and is adventurous enough to DIY, then you're in luck.
The Solution
Upon making in-depth searches on the web, I was able to put together a solution thanks to several different sources. Primarily owing this to a couple of fellas (members) from a now defunct car forum club3g. The guys provided very detail steps for the DIY replacement and more importantly identifying the Part Number you'll need to purchase the replacement part from a Mitsubishi dealership. You can download the PDF for the Step by Step instructions here. Good luck to you!