I would venture to guess likely, I can say that the old NES advantage was 6mm and I was able to put a JLF balltop on mine. Knowing how Nintendo likes to fall back on their parts, I wouldn't expect them to change sizes.
However, I haven't been able to remove the ball from my cab joysticks and am not going to try to really crank on them to see if I can crack them loose, as I think they are pretty cemented in there.