The one you would need is the plain faced one on the right in the photo. In the full crank models there was only 2 jets i'm aware of. The plain face for the 160cc and the 1 ring for the 125cc.
The s-600 powertorque runs a smaller jet and a larger diameter intake snorkel.

As for the emulsion tube, what clarification would you lke. Post up some pictures of the underside of the jet and carby where the jet screws in.