What camshaft should I use?

I have a 1970 Dart Custom with a 225. It has 111,000 miles and it’s never been rebuilt. I was thinking of doing a camshaft.

I’m looking for a good camshaft that makes a lot of vacuum, gets good fuel economy, idles smooth, and has a focus on low and mid range power.

I found a Hughes camshaft that sound good:
Hughes Engines

I also know there is the Erson camshaft, but it never seems to be in stock:
http://www.pbm-erson.com/Catalog/Erson/Camshafts/Mechanical Flat Tappet_E/ERSE470301