I currently own a 1985 60 and a 1996 80 with 1fz. Ive also owned a 92 80 with the 3FE. In my opinon, you will always be dissapointed with the power (or lack thereof - they are cool but slow pigs!) I agree with one of the above posters - go with a 95-97 80 series and cut the eventual corner. Especially with the children, I would consider the extra safety built into the more modern 80 series.
I love the "soul" of the 60 but whenever i get into the 80, it truly is night and day for power, handling, braking, quiet, smoother ride, features, etc. The 80 may look big but wheels small. With lockers Ive seen many 80's go places where others struggle.
Of course last but not least, get a mechanic to fully inspect any likely purchase and see what youre getting into. I fyou find a incredibly maintained rig that needs close to nothing that gets moved to the top of the list no matter which type Land Cruiser it is.
Good luck! please post up with whatever you end up getting.