alum
If you stuff is together and does not need a rebuild, I would probably leave it together.
Before your need the rebuild, save you extra cash up for a set of dart Pro 1 325 heads or RHS 320. Your engine could benefit from the larger intake port/valve and the weight loss wouldn't hurt either. I got a set of new bare 325 Pro 1's recently for $1300 bare. Maybe you will find a deal.
I know the heads you were talking about. They had damage and need repair and maybe will again after you fix what's wrong currently. Maybe those parts are not up to quality of the use they were put thru. I am kinda funny about buying other peoples problems. I wonder if they are jinxed or what.
I have a friend that is a Pro Comp dealer. He said he only sells bare heads, not assemblies. I bought a set of BBC Pro Comp polished cast valve covers from him. They looked good but were 1/4" short length wise and leaked even with a steel core gasket. If they can't build a valve cover right, what about Chinese built heads?