hey can any ine help me in finding out where i can get
Cylinder & Piston Assembly 46AX

i have already checked with ROTOR.co.in but there is no stock
i would be really intersted to buy if any one has a spare / or could tell me where i can get it from\

Sadly in overly price sensitive markets like India, reliable brands like OS and Futaba doesn't have proper support.
The Piston and Case assembly is overly prices to be replaced. Try on e-bay or best, Tower Hobbies. Shipping form Towers would be not much ($9 for this) and their parcels usually reach without custom hassle.

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNXD5&P=7

But I would still suggest you to eye for a used OS 55 Engine on RCG/RCU/Ebay instead of paying $100 for the Piston assembly.

Here is distributor list in India from OS engine website

http://www.os-engines.co.jp/english/distributor/list.htm#i

You can try to contact them.

Apart from Inter Trade( PaylessFlymore.com) all others looks institutional 'Supplier' to NCC/NAL etc - I have never heard anyone buying from them. I checked at Payless.. they dont have the Piston and Casing....