These specialized exhaust pipes with expansion chambers are very rare! I bought them in the UK and had to have them shipped here at a huge expense 5 years ago.
As any knowledgeable two stroker will tell you power from a two stroke comes from the expansion chambers and these ones have been custom designed to make your RG fly!!
I had planed on building my gamma up into a tour de force but unfortunately I blew the engine before I ever got a chance. I had always planned on getting a new gamma engine but never did. Now I need the money because I am moving to Germany for 6 months. My loss your gain
I will post pictures later today.