Supper--
You said in your first post that being able to buy ammo in a pinch was a factor in your decision. In that case, I think 308 is the best choice. The chance of finding 7-08 goes down, 260 even lower, and 284 way down.

You could buy 3 Kimbers for the price of a NULA, and sell the two that shoot the least well for a few hundred less than you paid.

I have a NULA, and like it fine, but if I were right handed, there would be some Kimbers in the safe.