The reason I will most likely put LA heads on a Magnum is due to circumstances. Several years ago I bought , for a great price, a 360 magnum that appears to be the 380hp 360 crate motor : single plane Mopar intake, "Mopar Magnum"finned valve covers, factory type car oil pan, etc . I intended to mic the cam to see if the lift matches the 380 hp cam but haven't yet done it. My original plan was to get the Enginequest heads but those have been discoed. Last year I bought Speedmaster LA heads and intake on their black friday sale. My hope is that the short block is in good enough shape that I can just throw rings and bearings at it. As far a good head availability, I don't really think there are very many magnum choices out there. I doubt there is anything out there for the 700 dollar price I paid for the SMs.