Dear friend,
To my limited knowledge, I don't think there is any organization in India either in Public sector or in Private sector having included " Marriage Leave" as a separate and special type of leave with wages/salary to be granted to employees in its Leave Policy. I also think that the same is the case in the rest of the world barring a few countries such as China, Spain,Poland, Malta.
The general practice in this regard in India, as I can observe, is that employees on the occasion of their marriage which is generally well-planned ahead, avail their E.L for about 10 to 15 days with the prior sanction of their employers.