Hi Soumik,
I did check out most of the retailers including chroma. No WP7 devices were available

. And yes. I do know that when flipkart, letsbuy etc mention manufacturer warranty, they mean that i should contact the manufacturer. I was talking abt the seller warranty that sellers mention on ebay. Here u will have to send your device back to the seller and the seller will now repair/give a new phone to you (Which is a bit hard to trust).
@krishnandu.sarkar
From what i could gather from my search, even HD7 isnt officially (with manufaturer warranty etc) available in India now. It was released early this year; but right now not available in the market. Just for reference you could check flipkart, letsbuy etc. its either listed as out of stock or sold out.
HD7 and Dell Venue Pro were released in India (Venue Pro featured in Bazaar in Digit May 2011 issue) but both arent right now available in any online stores.
Update: Venue pro is available on lets buy. But i am interested in buying HD7