This is a spur of the moment list posted after I happened by a list on Baseball-Reference of all the All-Star Game homers. The pre-1960 All-Star homer hitters are:
Augie Galan, Max West, Rudy York, Mickey Owen, Vince DiMaggio (matching brother Joe’s 1), Hoot Evers, Bob Elliott, Ray Boone, Gus Bell (the only Boone and only Bell to hit an All-Star homer), Frank Malzone, Jim Gilliam.
The question that comes to my mind is: How many of these names do you recognize? I hadn’t heard of a handful of the players.