Guys.... with all your guidance and support I could successfully solve my AIMCO M200 problem and not only that... I could do lot of successful experiments.
Special thanks to TIRTH

S
I could build my own spring compressor and could dismantle the gun completely with out any problem.
with the help of Mr.Domenic (Mr. Ganapati`s very senior gun smith) of KOVI shop I could get machined washer to my gun.
Had to struggle a bit to insert main spring in to position... but finally a sweet success.... sniper also gave some very valuable suggestion.
Best part is I swapped the stocks of my IHP and M200. Now my IHP looks fantastic and shoots pretty nice
I need to do some paint job to my newly modified IHP I ll post pics very soon. Now it is a real pleasure to even to hold my IHP. I have devised some mechanism to mount a laser pointer and as well as a dummy muzzle brake

.
another interesting part is I found out a very new way to get a very good quality air rifle.
Its simple and even I did it...

I purchased a local air rifle for 1,700 bucks (Asian Armory)and handed it over to KOVI for over hauling....

after a change main spring (G smith), washer (GS) and cleaning and greasing (Rs.600/-)the new local air gun shoots close to IHP. I must thank KOVI for giving me valuable tips and excellent product.
After all thanx givings...

now I am a owner of 3 really nice shooting air guns
here is the link to gallery
http://biaf.in/m200/
sorry for poor quality photos and they are not in order....
I dont know whether I did good, foolish or bad... but I am happy for what i have and what I did....

friends... further suggestions please...
Regards,
Krishna