Citizen, Your wife will love a Pinz. My wife even likes driving ours on medium rough trails.
I've had a 712 (6x6) for over 7 years with very few breakdowns, especially given the workout I've given it. They were designed to be fixed by 19 year old draftees: most repairs can be done on the trail with the tool kit it comes with. It is an extremely reliable vehicle. But it is 32 years old, so it needs more adjustments than a modern vehicle: carbs, valves, brakes. And like all of us old farts, it breaks down occasionally.
Parts are very available, though admitedly pricier than for, say, a current Chevy. The axle boots are also available as a split-boot, which does not require removal of a wheel unit. But the wheel units come off pretty easily, it's only a couple hour job.
Most Pinzes stateside have had the points replaced with a Pertronix ignition. The fuel injected systems seem to add 2-3K to the cost, but reportedly they are nice. This might be a bigger issue if you've got emissions testing. But if the carbs are working well, they work very well indeed.
The air-cooled engine is very reliable. Some people have had dirt build up around the head fins, which causes overheating damage. This seems caused by driving through deep mud or possible oil leaks around the engine collecting dust/dirt. Probably, the air-cooled design solves more problems than it causes.
I agree that body work is tough, but not necessarily impossible. You just need to be a metalworker.
I'd suggest staying with a 710 model (4x4) because it's cheaper (only 4 tires, brakes, etc. as opposed to 6!), faster (100 k/h vs. 88 k/h rated speeds), and cuter (according to my wife). Paint it yellow and it's a chick-magnet.
You might also check out a dealer in Wisconsin:
http://www.staufferclassics.com/ George is a friend/neighbor, and a truly honest guy. I don't know how many Pinzes he's got right now, but probably a few. There's also a handful of other people's trucks around if you want to test drive several (a good idea). We're all near Madison.
Chuck: did you see the orange Jeep-thing the guy has posted on Real4x4s and built on a rolled 710 chassis? It looked pretty neat.