These are probably the best suggestions so far, I might go with Swargamara or Meghalaya. Though is the "One Hundred Thousand Islands" put together Laksha Dvipa?
Again, I don't know what the proper grammatical form would be for Laksha Dvipa. This would be the literal translation or you could simply put it together as Lakshadvipa. You could also tinker with it a little to simulate linguistuic "drift" or corruption over time.
The modern Indian Union Territory of Lakshadweep derives its name from those sanskrit roots. Also Meghalaya is the name of an actual modern Indian state.