What's your budget?
We have a vintage Stressless chair and ottoman from about the late 70's, early 80's and it's still in great condition. It is sooooo comfortable. It does need a button restitched, but other than that, it's fantastic. We bought it used for a few hundred dollars about 5 years ago and it's been great.
From what I've seen, the Eames chairs, (my dream) used are around the $3500 range, or so. But there are some replicas that might be fine for you.
If you buy used, you can always get most, if not all of your money back if after a while you discover the chair isn't working for your back.