413 cylinder heads... are these toast??

I will be doing whatever is the most cost effective. And my plan A is to save these heads if possible. Currently the couple of valve seats that are serious rust are my biggest threat. I'm thinking I'll dissemble them, soak them in muriatic acid and then see just what I'm up against.

Previously on a 390 Ford, I was able break everything free and clean the seats up by just lapping them which it looks like I can do with most of these. They turned out pretty good.