Well I'll bite, I own an HZJ75 troopy and I used to own a BJ73. The 7X world is far, far larger and more complicated than the US domestic Land Cruiser world. Far more variety in engines, drive trains, options, etc. More to know, more to be wary of. First I would recommend joining the IH8MUD website/forum and get familiar with the 70 series section there, read a lot, search a lot, ask questions (only after doing your own research), etc. In the US it's "40 series, 60 series, 80 series, hundy" but in the 70 series world the variations easily go into the hundreds of vehicles and the variety of diesel engines alone can be exhausting.
This'll get you started:
Technicals are some of the most commonly seen vehicles in irregular warfare, and those based on the Land Cruiser 70 Series are the most prolific of all.
tanks-encyclopedia.com
Don't assume you'll have to go through the importation process. There are a fair number of 70's here now and more every year. You can't legally own/title/drive (although it's more complicated than that) a vehicle younger than 25 years (to the exact month of manufacture, not to the year) so you're restricted now to vehicles made in July 2000 or earlier, which is a lot of options. As time goes on we're going to see more and more "modern" 70 series trucks come in and your options will improve. Be prepared to pay heavily for these modern options. A V8 troop carrier imported here is going to be a major life investment unless you're rich but then a lot of people in "overlanding" are rich to begin with.
If you're ready to buy, one place to start looking is on the classified section of IH8MUD. This is where I bought mine. There are usually several good vehicles there, and the "mud" community does a pretty good job of policing its own ranks. This is not Bring A Trailer - there is real expertise there, and freshly painted bondo queens from Nicaragua are quickly torn to shreds.
The left hand drive vs. right hand drive issue is a big one for some people. If you're going to travel internationally, it can be a huge one. There are several countries that absolutely will not allow you to enter with a RHD vehicle - Costa Rica is one. There may or may not be unworkable insurance situations around RHD. My troopy came from Europe and is LHD, kind of a rare bird, but lots of 70's in lots of markets are LHD, you just have to seek them out. A lot - probably most - get imported to the US from Japan or Australia, which skews the market to RHD, and makes people think "all those trucks are RHD". They're not, you just have to look for them.
I'm not going to get started on the engines. There are too many to list, none of which were ever sold here and none of which you can easily get parts for with the exception of maybe the legendary 1HZ which has been made for so long, for so many vehicles in so many countries, that it's simply part of the Earth's crust at this point.
There is a section of Mud that deals with nothing but vehicle importation and there are several highly knowledgeable importers there. A good place to look for rust free trucks is Saudi Arabia and some other Gulf Coast countries, and there are some guys that specialize in this market, have friends and contacts, know of trucks, know good shops to get work done, get parts, etc.
And lastly, ask yourself "why do I want one." If it's for looks, if it's for Instagram, save yourself a lot of pain and grow up. If you just want a tough reliable vehicle to travel the western hemisphere in, just buy any used 4Runner from any Toyota dealership anywhere in America and be done. You'll have a far easier vehicle with a far better parts and expertise network behind you. Good luck trying to get an oil filter or head gasket for a 3B diesel in Guadalajara.
