Help ! need new piston for my 210 malossi


i recently buy a new 210 kit malossi by Sip, but got problem with the piston because too much advance.

Now i need a new piston but dont know if the malossi piston "211cc" "A" available by sip will fit in my cylinder.

Thanks for help !!!!

What was it originally? Was it "A"? If so, then wait till sip have stock or try other vendors around, PM tuning or other uk tuning shops.