Hey, I was just thinking if the supplier would tell you who else in Bangalore orders from them, you could possibly swing by and try to buy a small amount off of them before you invest in a 50lb sack. Maybe just say you'd like to inspect the quality or something.
You'll pay more per pound for the sample but it would allow you to experiment. If you don't mind sharing, how much are they selling the 50lbs for? I completely understand where you are coming from. I just finished a little over 2 years in Central America and am now heading to Eastern Europe for 2 more. When trying to find brew supplies you have to be creative!