The best manuka I have found in the US is at Whole Foods - it is Certified Organic and Active 12+. I found the same product at http://www.thewildbee.com.
It works like a miracle on my heartburn and acid reflux. We also use it on skin wounds and burns - takes away the pain with no scarring. It kills bacteria better than Antibiotics . It's the best thing I've ever found for a sore throat. Just can't say enough good about this product - especially the organic - because of the pesticides and herbicides in most floral sources and the chemicals and Antibiotics that are used in most US beehives. That's why we always get the organic.