I just noticed your question about a good source for jiaogulan. I order mine, 1 lb at a time from http://www.mountainrosehearbs.com.
I prefer their organic herbs (leaves)to the powder, as the leaves allow you to see the quality of the product. The leaves, once steeped in water for several minutes, open up and look so fresh, as if they just came from the field. Their tea has a pleasant sweetness which is quite enjoyable.