Hi there
You can easily order one online from ebay or similar websites. This RFID reader will cost you around 450-500 bugs but if you buy it from market, you can cut a lot in its cost. If you live in delhi, I would suggest you to visit Bhagirath Place, in Chandini Chowk. There's a shop named Everest Electronics (shop no. 644) which deals with such things and lot more stuffs as well. The shop guy is really helpful and he gives valuable suggestions, if you ask.
Hope this helps 