Originally Posted by
WizardOfBoz
Anything can be done! But I agree with you if you add "reasonable or cost-effective" betweeen "no" and "fix".
One approach is to reverse the dent with a plastic mallet on a bag of lead shot and once you have tire clearance, just ride it.
Well, sure. It'll still look like ass, but will be functional.
But I think the OP is interested in aesthetics -- in which case, the only solution is to get new fenders, unless a single replacement can be sourced.
I like the suggestion of a sticker. Maybe some reflective tape, which is nice on a rear fender from a safety standpoint, anyway.