A PCV valve AND a breather on each valve cover, with both PCVs on a T, might help. Other than that I'm afraid you're talking about an overhaul. It's obvious that the rings are letting to much compression slip into the crankcase. Hmm... with so much going past the rings, maybe two PCVs and no breathers will be okay.
Check the bottom of the valve cover though. There should be a baffle that keeps oil from going directly out of the hole. At least most cars have a baffle there (usually just a plate over the hole with space on each side between the plate and valve cover to suck in/out air). I know that AMC V-8s have a problem sucking oil up the PCV when the baffle isn't installed (it doesn't come with most aftermarket intakes -- they expect you to pull the factory baffle off the original), but they pull the PCV from the intake instead of valve covers.