While there might be very little danger of it happening, please don't take any of the following as gospel. We can only go on experience and there will be lots of different opinions.
Generally, the best advice on buying a Nissan, if you really want it to last, is to spend the extra and get a Toyota (lol). Though all (half) jokes aside (sort of), the D22 is generally a very good, tough little ute. The motor is generally good and the drive train seems good also, perhaps except for the front diff if you want to do much 4wd-ing (not a Nissan problem, seems a bit small and weak in all these type of vehicles). The front suspension is crap, but I still far prefer to drive one of these than a hilux.
I would buy one with that many km's on it, though as with all used cars, there is a risk. Then again, plenty of people drive complete lemons out of the showroom (even Toyotas).
If it's been looked after, that's not a huge amount of km's at all and you should get quite a few more years out of it. If you know someone who is used to them, a lot can be learned just from starting and listening. If not, you will have to rely on your own evaluation. Check for all of the usual things like oil leaks, strange noises. Don't worry of it takes a few seconds or more for the oil light to go out (when starting cold), not uncommon. Take it for a drive and find somewhere to put it in high/low range and 4wd to listen for transmission noises. Give the chassis a bit of a look at the stress points.
While many of the problems mentioned above could happen, that doesn't imply they will. A lot depends on how it was used (heavy towing etc). A good service history will help, as a lot of problems come about from lack of servicing. The fuel pumps can suffer if the filters aren't changed regularly. The oil needs to be changed regularly not only for the motor, but it lubricates and cools the turbo.
That's something (IMO) that is likely to be a bit tired with that amount of km's on a stock Navara (the turbo). Mine was basically clapped out about 170 thou. Though it didn't let me down, just lost a bit of go, new turbo and all good. At any rate, people rarely get rid of cars because they are going well (though some do simply update) and it's possible it could need some work. The idea isn't necessarily only to see if anything might be wrong with it, but what work might need to be done. It might not be much. There is still every chance you will get a good reliable car, even at that amount of km's.
Anyway, good luck with it.