Some of the stems from back then seemed to be made to fit Varsity clones having 70-degree HT angles and .833" (21.1mm) steerer ID.

I notice that one such stem, branded "Compe Forged", has a very noticeable downward tilt even when fitted to my American/Nishiki Kokusai with it's 72-degree HT angle.
It's the original stem as I recall, I recall having bought the rough, old bike for $20 just to use it's 110mm stem on my Schwinn Supersport, but found the bike's style and configuration as a rider too compelling to part it out!