In ebay you are seeing the lowest price, on the street in kolkata, its very hard to find the lowest priced shop. Btw, I have seen common gadgets or accessories are better to be bought from ebay, due to its sheer number of products availability and transparency in price .. Also don't forget that everybody is not a good bargainer in shops. To top this up using a coupon code sweetens the deal further.
Note: Check for Manufacturer's warranty coverage and the sellers ratings before you buy.