How about Orcusananda? Barring that, I kind of like the name Mahakala. It isn't exactly an evil deity, but is a compound word of great (kaha) and black (kala).
Or even just Orkala--that sounds Sanskrit, and you could say it means "black-soul" or something like that.
I'm wandering slightly off topic here. Sanskrit is a satem language, so the "c" in Orcus would be rendered "s", assuming a common root. An etymologically authentic name would be something like "Arsa" (or "Bharsa" if Orcus came from Celtic - the Greek is "Phorcis" IIRC).
With that bit of idle speculation out of the way, I propose "Bharaksha" as an Indic-looking, sinister enough sounding name.