Magnum replacement heads?

I have read somewhere that EQ discontinued their magnum replacement heads? Upon searching I've seen Speedmaster and Promaxx have a replacement Magnum head. Does anyone know if they are all about the same castings? I'm trying to build a real LOW budget 360 for my pulling truck for next year and the magnum replacement heads seem to be the best bang for the buck. Another question is does Indy still offer their line of LaX or MaX heads? I thought I seen they were discontinued as well.
Hughes has stock replacements on their site with bronze guides for $1250. They say their Iron Rams are discontinued however