Firstly, it is very easy to remove the bezel and insert, and then the pearl can be removed by gently using a small screwdriver and a little leverage from the edge of the bezel. The pearl is simply glued to the bezel, and it comes off easily.
The second part of the equation is not so easy. The ebay bezel that you posted does not look any better than the one on our reps. The pearl still sits too low, and it is not shown clearly enough to determine the quality of the pearl itself. I'll warn you that these aftermarket bezels can also be slightly smaller than the rep one, leaving a slight gap at the edge of the bezel.
As far as I can tell, the gen has a similar set up to the rep, where the pearl protrudes through the insert and not simply sitting on top of it. I have done several mods to the pearls on my UPOs. The have been removed and re-glued so they sit straight in the insert hole. I then used a fine grained sandpaper to grind down the glass, as it was sitting unevenly in the pearl cup. The glass and silver ring were then polished with a dremel. The pearl is still low in the triangle, but other than that it looks good!