cylinder head rebuild

OK if I ask a few questions too?

1964 225, freshly bored/honed +.040.
I guess for now I'll be sticking with the 64 head. I'm on board with the .100 off the head.

The original head gasket I took off was steel. (0.020?) Are they still available?

Pushrods: I read that stock ones can be reused. Is it necessary to get shorter ones?
If going with stock length rods and longer aftermarket adjusters, does the top of the rocker arms have to be milled for locknuts? It seems it would be almost easier and maybe cost effective to just get new pushrods .100 shorter than stock from Summit. Just give them the length and they make them.

If using a composite head gasket (Felpro), isn't that going to be thicker? Like another .020 or so? So it would lose a little compression using a thicker gasket.

Wild Bill Dedman and Pishta have me thinking a turbo may be in my future in another year or so. So, not a good idea to mill the head if a turbo is in the future?

I need to work this out so I can be on the road for spring. :)