I know your pain Im going thru the same dilemma I
if u 30 over I have a good part # for ya !!!
My 69 model block needs to be bored to 4.080 and options are thin for 40 over in high compression.
You can buy a TRW piston with a dome on it that you can cut down and set the compression where you want it. I can't think of the part number now but I used them in my last build. The weight means little to me.