I replied to your PM with a couple of comparable trucks in Minneapolis that you should consider as well.
As for the engine / transmission concerns, for vehicles in your price range (older, higher miles) the reliability of the Toyota brand starts to become less of a factor than how well the previous owner took care of it. A Toyota engine that doesn't get regular oil changes will still fail. With that said, most Toyota owners bought them because they are reliable, and understand that they stay reliable by being well maintained. But it is something to consider when talking to a seller.
For engine / transmission concerns, the 4.0L engine and 5-speed automatic transmission in the FJ are shared with the 4Runner and Tacoma and are absolutely, positively bulletproof. Between the three models there are well over a million of these drivetrains on the road. I would prepare for a maintenance bill for whichever truck you buy -- front/rear differential fluid, transfer case fluid, transmission fluid, engine oil -- but otherwise you're fine.
These are great vehicles for the snow, they are not full-time AWD but rather 4WD and will need to be put into 4-High when you hit traction problems. So just be mindful of that. The manual-transmission trucks are full-time AWD if that's a concern to you.
Alternately, if you aren't buying the FJ to offroad then you might consider a Tacoma instead? For the same year / miles a Tacoma should be a bit cheaper (my wife and I paid $8900 for our '99, 113K miles, V6, 4x4). The FJ is a unique and interesting vehicle but is overpriced for a daily driver. Don't get me wrong, buy one

but if money is a concern, there are cheaper, just as capable / reliable options out there.
Happy to help, let me know if I can answer any more questions!
James