I think you are right not to touch those NSK rails, the damage is way to close to the bearings for my liking. There are some HiWin and THK clones over on AliExpress that looked ok and the reviews I've found are generally positive.

Does the power supply really have that written on the top? I can't quite tell if it's been "photoshopped" on. You certainly wouldn't mis-read the spec.