The seals for a 68, 69, 70... are all the same. They only changed HOW they install. Later ones go in from the front. Just get one and pound it in. Don't overthink it.
One has the seal install from the front and one has the seal install from the backside. That new one is like the later model version (76-and later I believe?) which installs the seal from the front.
I've had good luck with Engine Pro sets. I've only been able to get them through engine shops though.
https://www.enginepro.com/downloads/newdata/EPG_TimingSets.pdf
And to think, when I was just getting into Mopars as a kid, these types of discussions were reserved for the E/B-body crowd. I'd never imagine A-body folks needing a correct exhaust heat shield. Don't forget your roots, guys. :poke:
Seriously though, I wonder how many of these are sitting in...
I called Schneider cams recently. They used to resurface lifters, but don't anymore. According to the gentleman I talked to from Schneider, hylift johnson lifters are pretty good and shouldn't require any type of surface correction.
I've used permatex black, gray, orange (high heat) on LA china walls all with great success. As long as the surfaces are clean and oil free, any rtv product should work fine. Nowadays, I favor the black stuff.
It'll still work. It doesn't need to be flat against the balancer. In fact, you just need a couple bolts on opposite sides. Just make sure they're long enough.