Metal knobs are prone to scratches and dents too, particularly if you don't take any (wedding) rings off. When I bought my car (demo model), I insisted they replaced the knob for a new one because of this.
AFAIK, you cannot buy 'just the knob'. It cames pre-fitted, so you have to buy the whole gear stick! If so, that's not a quick swap-over job, and not going to be very cheap. (if you find out otherwise, correct me)
Shiny, that momo handle doesn;t look bad at all, whats the quality like? How easy was it to fit?
Quality is very good, and as good as OE. Though I fitted the exact same to my 155, but have had two minor issues: I over tightened one of the Allen key grub screws, so cracked the area around it, and the chrome garnish near the knob worked loose (glue failed). But no big deal.
The factory gaiter does NOT fit properly around the base of the MOMO handle (factory = too small circumference), so you are best to have a matchin gaiter. They offer a model for exact fitment.
The original is glued into position. If by chance you wish to reuse it, I suggest slicing it along the underside with a utility knife, then peeling it off; you could try a heat gun, but you'll most likely need to cut it one way or another.