I'm planning on traveling to Myanmar, Thailand and Vietnam with my drone (can't leave it home because I'm actually going home through this countries) and I was thinking on buying this "Letters of Authorization" on this site www.uavsystemsinternational.com. Had someone tried them? Is there another way I can obtain this certificates? I mean for Thailand should be easy once I get a third party insurance, but what about the others? Myanmar and Vietnam. I tried looking on Google, but I couldnt find something that works.