Infosearcher, in the absence of a nation wide database of licensed gun owners, it would be next to impossible to get the total number of licensed gun owners, let alone find out specifically how many of them are licensed shotgun owners!
While many local licensing authorities are now computerized, a large number still use the traditional paper/ file system. It might be possible to get figures for a particular jurisdiction from that particular licensing authority - but compiling a nationwide census would be a herculean task! I doubt if even the Govt. of India has the exact figure of how many licensed gun owners there are in India
Finding out the details on the number of licensed arms dealers might be a tad easier - as I believe the data should be with some mandarin or the other at MHA - you would still need to convince him to divulge those details though!
Sukhpreet, you reckon the Right to Information Act could be called in to the rescue here?