[Aussie Mike]

Don't know what brand the rotors are. Haven't been able to find any identifying marks on them.

Changing the PCD is dead easy. A 10 minute job once the disc is set up and trued up on the rotary table.

I'm pretty confident the hats were made from cut down 1 piece rotors. Especially given they are made from cast iron. I'm thinking they may have been Holden going by the larger PCD they came with.

I'd be happy to help you machine a set up if you want to give it a crack.