It depends on whether you like the "used" look, or you are wanting a museum looking piece. If the paint has just recently fallen off, look on the floor for paint chips - unless you vacuum every couple of hours, then if they recently fell off, that's where they will be.

Personally, I look at all my machines with a "Does it work?" lens. Once working, then I worry about how it looks. There are lots of threads about repainting cabinets on this forum. If you don't want to go that far, mix some acrylic paint and touch up the spots if they really bother you. Better yet, buy another machine and put it next to that one - if they are close enough, you won't see those spots!

Leave it, the touchup will almost always look worse unless you're really good at color matching. Just check your game periodically against this photo you took and see if the flaking gets worse. These games are 40+ years old, wear and tear is inevitable, even in the hands of collectors.