Personally, I like the older style TJ mirrors.
But yes, all the ones I see, the metal part on them seems to be corroded.
To tidy them up, I take them off and hit them with a flat black rattle can. No prep, just spray the metal part. Take them off, spray, Re-install. Takes about 15 minutes.
Had my TJ 2 years and to do it twice so far.
Seen all sorts for sale on all the usual Jeep vendor sites but never bothered because they look great after being sprayed.