I have a set of J heads with 68cc chambers, I need 62cc to reach the 10.4:1 compression I need. I already have a set of Cometic head gaskets .060" which I will use. Has anyone milled them that far?
I paid $140 for an 0.005" cut on both heads a few months back. You will need a few passes to get them down to 62cc.
Serco in Capalaba will probably make you a thin set of cometics for less than the machining costs.
But a cheaper thin composite gasket will probably do the job for much less.
Hell you might even be able to pop the rivets on the 0.060" gaskets and take some layers out to get down around 0.028" thick.