Astral life vests are good. I use the Newton though it is not USCG approved as a PFD- "bouyancy aid" because it doesn't have the requisite bouyancy to be a PFD.

as far as harnesses... hopefully you have a dealer near that carries them and can try some on. My wife did this at Key Sailing in pensacola. Tried on about 6 before she settled on the one she wore only once 2 years ago.