Unless Westploy/Southploy become named CJOC missions I doubt there will be a medal issued. Going on a CJOC mission means that there are much tighter controls on what you can do in port(Ie; Hotels and drinking), so you really have to ask yourself whether you think a piece of ribbon and a bit of tin is worth losing out on your freedom in port. For my part I prefer being able to see new places and enjoy the local libations more than I would enjoy a shiny new gong that means nothing to me.
The whole purpose of the SSI is to recognize the amount of time spent away not on missions. I think given the nature of Westploy/Southploy more days on the SSI is more than enough compensation.