Many of the more modern Indian sets are camel bone - but pre-ban (and
for a while afterwards) they used ivory quite a lot, as there would
often be 'left-overs' from larger carvings. I did wonder about your set
as, although I can't see any Schreger li...
A relatively similar set has just appeared on eBay US
http://www.ebay.co.uk/itm/VINTAGE-INDIAN-BONE-CHESS-SET-HAND-CARVED-PIERCED-31-p-FITTED-CASE-20th-C-INDIA-/261393406884?pt=Games_US&hash=item3cdc42dba4
I tend to agree with the seller - mid C20th....
Modern versions like those are generally of camel bone, but the set in
question (and the cae especially) looks older (probably post WWII,
1950's or such ) - the composition is difficilt to see from the the
images.