I'm about to hit 200k and I've been offered $6500 for it once, and $6000 by two other people. Now, that's a truck that spent most of its life in FL and HI, and with a new set of wheels and tires and the offers were coming from the salt belt but I turned them both down because I don't think I could replace it for that. Nice ones pop up on CL and disappear the same day because people are searching far and wide for them.
The reason you're having such a hard time finding one is that they're getting harder and harder to find in the criteria you're looking for, and there are more and more people who want them. That's driving the price up. Remember a used car is worth exactly what someone is willing to pay for it.