I can't help you out for the live one, but do you have dried one ?
I bought my first brick ever of dried moss and since I've used it several pots have green spots now appearing. Even though it's not a 100% certainty, a lot of time it will revive from dormant spores which are in the dried/dead moss.
All it needs essentially is one spore to be alive and it will start from there, sphagnum produces like millions of spores or something, I'd try it if I were you
Otherwise, hopefully someone from India will step in to help you out, live sphagnum is considered as a live plant and normally permits and all the enchilada needs to be obtained before importing...you're really better off to try the reviving moss trick !