about 19-20HP bro (factory standard).
The expansion chamber is custom made but i replaced the silencer with "AHM", Malaysian Manufacturer for aftermarket and racing exhaust parts. The original silencer was like this... (longer, about 27cm)
If you like high rpm, this exhaust is good. But not recommended for drag bike.
I think RXS-RX115-RX135 standard chassis is not supported if you want to install this kind of exhaust. For those bikes, i recommend this...
about reeds, buy a set of new reed valve, double and glue it with the old ones. Do the same thing with the other one.