Vehicles that are Rust buckets here are old ones that were didn't have rustproofing like most vehicles in the last 20yrs. HMMWV's body is Aluminum, yes Frame is Steel. I've got two over here and the rust on the frame or suspension components isn't bad at all. There are more Army vehicles than Marines here by far, Navy and Air Force only have a handful. The Army vehicles mostly come from up on the hill, Schofield barracks, it is away from the coast and it rains more up there and is a little cooler. I'd be happy to take pictures of mine. You can read elseware about my bad experience with one of mine, misleading GovPlanet ad. Mechanically my other M1097A2 is a runner, 2005 I got for $3700.
As far as shipping goes, Matson is limited on scheduling but I've been using Pascha Hawii. Mainland (WA state) to hear is about $1700, not sure about HI to the Mainland.