Malossi MHR silencer with different exhaust?

Hi all, i have a 2003 piaggio zip sp with malossi 70 kit, malossi variator and jetting/rollers etc to match.

I am thinking of purchasing the MHR silencer Will this be able to fit a different exhaust system as the description states this only fits gilera`s. What is the diameter of the silencer chamber. Which exhausts would this silencer fit. i am looking to buy a cheap exhaust for this i.e. leo vince tt?

Hope you can help.

Regards, Lee