Early A-Body Automatic Transmission Switch

I have a 1965 Doge Dart with a 360 engine and 8 3/4 rear. It is currently a 3 on the tree and I want to switch to an automatic. I come into a lot of stop and go and, call me old, I'm tired of all of the shifting. I just want to cruise.

I was hoping to go to a 5-speed automatic instead of the normal 727 3-speed.

Any comments or recommendations?

Thanks