A fairly good slideshow of Rat Pack fashion, to accompany a story that the Sahara in Vegas is closing:
http://www.latimes.com/entertainment/news/la-ca-0116-rat-pack_pictures,0,892569.photogallery
Some of the jackets on those guys are real bum freezers
I think with dressing like the Rat Pack, Mad Men and a non-sissy version of Thim Brown, the attraction is one of having a theme. Most of the dressers I've admired always had a theme even if their clothes looked dated. Thus, you see a guy in very well worn suits with narrow lapels and when he shows up in black tie, the lapels are still narrow. Themes create ownership of look, and also that predictability creates comfort in the observer. Predictability doesn't have to be mundane, it could be for instance, that you wear a different shirt every day.
Even more Rat Packin'. Some of the same shots, but some new ones as well:
http://www.telegraph.co.uk/culture/culturepicturegalleries/8271833/The-Rat-Pack-a-book-of-photos-of-Frank-Sinatra-Dean-Martin-and-Sammy-Davis-Jr.html