Ted, it all depends on what will make you happy and you'll enjoy driving.

If you want something that has power and handles and you want a few creature comforts like A/C a late model Hemi powered Challenger is a blast to drive.
I love my 2010 Challenger SRT with the 6 speed manual trans.
It averages over 20 mpg and so far I've got a 13.15 at 106 mph out of it in this hot humid weather.

If you want something old school, the body style will have a lot to do with cost.

You might be able to work out a trade with someone with your 64 to get something.
It never hurts to ask.