I think the issue of morality/immorality of getting one's sef fixed up depends very much upon the reason why thi person is getting a plastic surgery in the first place.
Some plastic surgery is necessary to correct defects that cause a person more trouble than just vanity. Such as people with extra fingers can't wear gloves.

People who have been severely burned are sometimes in a great deal of pain and the plastic surgery repairs that. There are other changes similar to these.