That kind of mileage is an R50's heyday. My '01 has 116k and runs great! Like the other's have said, it doesn't really matter what much trim you go with. And yeah, they're good for some light off-roading. Some stuff you could get would be lift springs. There's a few routes you can go. Old Man Emu (OME) is available through ARBusa.com or ruggedrocks.com, Automotive Customizers has some @4x4parts.com, or you could go with Ironman @ camel4x4.com.
You could also look into getting armor like rock sliders for under the door panels, skid plate, a heavy duty bumper if you can find one for sale or you could have a shop make one for you. And also look into getting some all-terrain or mud-terrain tires.
Just look at the pinned topics.