O miles? Buy it, snatch it up!! I have a Sixty-5 model I purchased in Sept. of '04, (the first year for the Sixty-5), and have 14K mostly trouble free miles on it. Adjusted tappets a couple of times, haven't touched the timing, it runs great. Changed drive chain somewhere around 10K, put new tires on last Sept, aand am getting readyto install the disc front brake.
The Sixty-5 (as I understand it), is no longer being produced, although it was all about a different look anyway. That, and the fact that it was the bread that introduced the 5 speed gearbox sandwich. A very nice improvement indeed!
I wouldn't hesitate to buy another iron jugged Enfield, but for the fact that you can only ride one at a time.
DeeJay is correct, nurse the break-in, massage it gently for at least 1500 miles. Don't rejet it, put any performance mods on until you are satisfied with the break-in.
Ride it inthe early morning or evening, kkep it cool and vary the throttle always.
You will be miles ahead in the long run.
Good luck and have fun. Keep us posted.
Steve