He is getting very old, and not open as much, but there is a shoemaker on Carlos Calvo, between Defensa and Bolivar, in San Telmo, who makes shoes to order.
He is right next to the great Bondiola and Churipan stand. Look for the line.
An Argentine friend of mine makes some fabulous shoes, Im not sure if every man would wear them, but I do know of a few men who do. They do not have a store yet, but they do deliver free of charge with in the capital.
here is their website. I hope you enjoy! www.13calles.com