In that price you are looking at a YJ or TJ. Personally I'd go TJ, but that's prolly b/c its what I own.
Look for a D44 rear end if you go TJ
I suggest the I6 (4.0L) it has a little more power and same mpg.
personally I avoided modified Jeeps, as you never know how skilled the modder was, or if they 1/2 assed it. (that is until you start pulling it apart.)
You can look under the Jeep for scratches on the skid plates as a sign of offroad use (which can mean abuse, but doesn't always mean that)
High Mileage shouldn't concern you, as 200k is no problem for the 4.0L as long as its not abused to an asinine extent.