Can someone suggest an exhaust for a 139QMB?

My skeleton scooter, Drutt, is running fairly well. Took out half of the rollers from the variator so I can now go faster than 10MPH uphill, got an 85 main and no air filter (because the cone fell off, new one is on the way!), and now I can get over 35MPH on the flat. The next thing is the exhaust. The original one is rusty as a very rusty thing anyway, so can someone please suggest an upgraded exhaust that will fit a GY6 powered Twin Shock scooter? Looking at those available on Pedparts they only fit the single shock scoots: Is that definite, or can it be "Made To Fit"?

 

Forget the last post: I just blew it up.