The more specific you make your wants, the harder it is going to be to find, but "your Jeep" is out there.
I also had a specific list and it took me awhile to find, plus I extended my search. I found mine own Charlotte NC CraigsList, had a local friend go see it, then I made a trip from north Texas to get it, 6 states, 1100 miles away.
The 6cyl was one of my most haves. Many have the 4cyl, and with proper gearing, can still have power, but your have to run high RPMs to get it and you loose hi way speed. My suggestion is go look at and test drive as many as you can and make your own decision on 4cyl vs 6 cyl.
Auto trannys are desired by many because of better off-road control. For me it was manual, I don't off road and just liked the driving interaction. My TJ is not my primary vehicle.
Engine size, tranny type, color, are just a few of the options Wranglers have, as do other vehicles. Different than any other used vehicle, you also have half/full doors, soft/hard tops, stock/modded, etc. I found that buying a used Jeep much more difficult than any other vehicle.
Be patient, you'll find one, and don't be afaird to expand your search area to get what you really want.
Don't know what your budget is, but here's one. Silver, 6cyl, auto tranny.