I recently found the other missing part of the screen used shoulder pads. The screen used shoulder pads use a combination of two Jofa motocross chest pads.
Usually, the Jofa pads have just the lower portion of the shoulder pad seen in the movie; the upper round part is completely different looking Well, I recently got a variation where it's the other way around. The upper portion of the pad matches perfectly with the screen used version. I'll post some pics soon.