The other option was to look for Sazgar 200c water cooled engine. So i inquired and it was available for 35k. But as i call'd @feovo he told me to not to go for sazgar as the engine quality is not upto the mark.
What he suggested is to use saazgar piston in Ravi Piaggio and it will be good to go as he himself is using same set up from last year and completely satisifed.
So i went to one ustaad here in Quetta and discussed with him matter in detail. Here's what he said
Dont go for Zarang (Afghan) engine, the engine in piaggio is better than that one
If you want to do alteration just use chamber and piston of Zarang.
Bike will be "Goli" with topspeed of more than 120km 
Total expense will be around 7k
@vickytulla now looking for you expert opinion on whole scenario 
'