NO SERVICE on my iphone

Question

hi my name is amit and i am a iphone user in new delhi, india. i got my iphone from US a month back. It worked fine for 2-3 days and sudenly said NO SERVICE. the experts here say that there is a part called RF-PCB that needs to be replaced and then the iphone would work properly. pls pls pls help me with this so that i can start using my iphone. where can i get this part i am ready to pay the price for the same as far as it rectifies my problem.

many thanks
amit
[phone]