Several years ago I met a Viet Q that runs some hang gliders in the South, he received the first VN Private Pilot certificate, there was a write up in the newspaper about an ultra light that he built as a school project.
I don't have have his contact details, but he would be someone to contact, he owns a few ultra-lights, the first one made from parts that he smuggled in from the states.
If I come by his name I will post it.
Cheers, D.L.