Parts are expensive for a Paj / Shoggy, but they don't break down often. Blue Print parts are now commonplace too.... Dealers are even taking Paj's in now.
Buy the import paj and have Dual AC, Leather heated seats, no rust (Although you should underseal it when you get it) and that happy feeling of "When I turn the key, it's going to start" :D Check for the LSD on an import or an elec locker on the Shoggy for the rear.
Would avoid the 2.5, and for the sake or 4mpg I'd get the 3.5V6.....
Got a 2.8Td at the moment and apart from needing new glow plugs at the moment and a seal in the diesel pump went a couple of years back, it's been no problems at all. Even with playing in the mud. Downside of playing with them in mud is the Alternator is mounted low and no aftermarket ones (that I can find) (had a sticky brush on ours recently but washed it out and it's been fine since.)
Now, if you want to Modify it.... then a Landy or Jeep every time.... In hindsight I'd prob get a Landy as parts are so easy to get and can be got from loads of places.... Lots of "Landy Specialists" around... only about 8 decent Jeep ones in the country.... But get the LWB Disco, that way you have somewhere to put all the bits that fall off :D