Since I received a ton of great help on my last post...Here's one more.
Upon tear down of these 360 J heads I noticed this underneath the valve. Are these junk or fixable in any way?
You are going to have to have new seats installed.
Any decent automotive machine shop can do it, and fill you in on all the details.
If a seat like that comes loose and falls out it will destroy an engine in a hurry.