I think with VAT and all there should not be that much price difference. At least I did not find it much, when I bought my LG 3D Led TV in Bhubaneswar some time back. Although their after sales service is good, still I would advise you buy from the place your niece would be living. Also it would be much easier to transport it.
I think, better gift her a good LED TV instead of going the 3D way. There's hardly any 3D content out there and looks like this will carry on for a while. You can't always watch 3D movies with 3D goggles on, and watching 2D content on a 3D TV doesn't justify the premium. India just started moving towards HD and still we have about 30 odd HD channels that too at exorbitant prices, leave away 3D for a couple of years in the scene.