This rig (depending on rust, and overall conditions) would probably do you just fine. A bunch of guys here in Chile run with the 1st gen troopers. And they use them for more than just a mild off-road use. Getting the 285's on it will require a slight lift (not my experience but that of guys on
www.twistedandes.com). Still, I have to imagine that Guatamala is kind of like Chile, in the fact that cars, especially 4x4's, are much more expensive than in the states. A shackle lift would do for the tires on the rear leafs. I'm sure any maestranza can hook you up with something for around $30 u.s. and the front (assuming the torsion bars aren't too weak) will give you the lift needed by the cranking of them.
As a side note... A bunch of guys like this body style here in Chile because it's bigger than the 2 doors in the U.S. and there is a ton of space in them. Guys in Europe say the 2.2 is a little underpowered, but good. Once again, all of this is with the idea that the motor/rig is actually in somewhat of a decent condition. Another bennefit to owning a Trooper in South America is that they share almost the same exact chassis as the Chevrolet Luv crew cab pickup, so a large majority of the parts are typically available. Still, even if it's a good price, go to some local parts stores and ask if they have parts for that vehicle. I can get about 70% of the parts needed for my 2nd gen in chile for drive train, and only about 25% for my body/asthetic. So, I do a lot of junkyard internet buying and U.S./Australia importing. That's just because I'm in Chile though. So, check out the parts sit. before you buy it too.
FYI. Same goes for the Hilux surfs here in Chile. Not all the diesel parts are available, w/o importing thru the dealership. Once again, don't know how common they are in Guatamala. Also... If I was to buy a 1st gen troop like that in Chile, it would cost me $2600 to $3000 min. So, I find that the price is probablly about right, but do to the conditions it's probably been thru, try to get them down to $2000 even if you can.
Just my $.02 worth. Hope it's helpful!
Let us know how it goes.