Apparently, it's been too long since I posted the last message, so I'm not allowed to edit it. Silly rule.
Some examples you can check out:
1) 92 YJ Hardtop, rebuilt engine
2) Nice 95 YJ, hardtop, 138k miles
(equals 8.1 miles driven per year)... I actually really like this one. Go look at it. The mileage is super low for a YJ, and it's in great condition!
3) 97 TJ for $5.5, 4.0 engine!
Has 165k miles, looks like it needs a bit of TLC but would be a great starter... would need to look for a hardtop on CL, which is easy enough to find.
4) 98 TJ 146k miles
Needs a hardtop as well. Looks nicer from the outside, at least.
5) 94 YJ 130k miles, hardtop
Already lifted, winch, etc. Looks like some minor damage to the front fender there. Could be an indicator of something more serious, but could just be minor body damage. Easy to find a replacement at a junk yard. Just an example of a YJ that's already had work done to it.
Basically, if you're desperate for an engine under 100k miles, it'll take time before you find one. The 4.0 is a good engine though. You'd be amazed just how long it can run. A Jeep with 150k miles still has plenty of life left in it. Chances are, if you find one that's bone stock, it hasn't been taken off roading (at least nothing serious, and not very often), so it's less likely to have been abused. The cheaper you go, the more likely it will need some work, though. Also, if you're looking at Washington-area Jeeps... beware of rust. If you can travel at all, you may want to start looking at Jeeps that have lived their lives in the desert areas. Less likely to find rust where there's no humidity. =) Oh, and since you're military, you might look at dealerships. Many dealerships seem to offer military discounts, even on used vehicles. Just some things to consider.