Are the distributor gears aluminum or iron?

I'm probably going to end up just bringing it to a machine shop this summer. Knowing me it'll end up with a full rebuild.

I'm just weirded out by the fact that I put so many miles on before noticing the metal. I can't believe the rods aren't knocking like crazy by now.

I wonder what a rebuild will cost on an engine like this. Parts are still available readily and the engine is used in forktrucks still.