You might enjoy perusing the threads in my Zongshen ZS200GY-2 sticky, posted at the top of our Dual Sport Forum.
http://www.chinariders.net/showthread.php?t=6051
I recommend the FMF Universal Spark Arrestor; it works great and is the least expensive.
You should be able to find a used, Yamaha, XT225 exhaust header on eBay.
__________________
Spud
"Never argue with an idiot. He will drag you down to his level, and beat you with experience."
Mark Twain
2015 Zongshen ZS250GY-3 (RX3)
2006 Zongshen ZS200GY-2 (Sierra 200)
2005 Honda XR650L
2004 Honda CRF250X
1998 Kawasaki KDX220
Mods made to my Zongshen ZS200GY-2:
http://www.chinariders.net/showthread.php?t=6894