I'm at work now, but I actually own a program from the 'Night of Helmets' at Miami jai alai in the early 60's I'll provide the exact date later when I go thru my programs. It happened immediately after the great Orbea took one on his head which nearly killed him. In the front of the program was a little message to the fans about this jai alai first and how players had been experimenting with such a helmet in practice. Soon after it was adopted in all frontons in America. I'll provide more info in a couple of hours.