Can't comment too much on the area or what gear to take but there are plenty of threads about insurance floating around here. I've used insure4less in the past as they have a specific policy for climbing with two levels: One being cover for sport (fixed pro only) and the other for trad and alpine. So your choice of policy will dictate what you can do over there.
I think the climbing areas in vietnam are mostly bolted but I'm sure someone who's been there will be able to clarify. I've also heard there is a plenty of deep water soloing around so you'll probably be able to a lot without having to carry trad gear.
One thing to consider when climbing in any of those regions is that you don't really want to have to use the medical system. So you need to be confident in your abilities to climb independently and safely and to assess the reliability of protection (bolts and all!). All just common sense really.