You can't get them in Mumbai.
Direct imports or sample programs are the only way.
RS/Farnell is expensive, beyond reason. Their prices are usually original cost + shipping cost + 80% profit. They may come close to D-K prices if you order 15,000 or so.
Edit: The Farnell price on the LT1364 is not too shabby.
Edit 2: You be careful with those opamps. They need lots of compensation. Such high-speed amps usually have stability issues when you drop them into circuits that do not properly compensate the output.