Custom free allowance (except for passengers returning from Nepal, Bhutan, Myanmar, China, Hongkong and if not mistaken from Pakistan also) is : Rs. 15000 if stay abroad is less than 3 days. Rs. 35000 if stay is of more than 3 days.
Online source is:
Duty Free Allowance and Entitlements - Indian Residents and Foreigners Residing in India
Online source is:
Duty Free Allowance and Entitlements - Indian Residents and Foreigners Residing in India