Combustion Chamber size

A friend of mine is building a 350 out of a '70 or '71 4 door chevelle. We where wondering how big the combustion chambers are. I'm thinking around 69 cc's. I saw several numbers on the heads so I'm not sure which is the part number. But here they are: 462624 and D138 also therse was a GM and then a 6 with a rocker mount between the two. Any help would be great. Or tell me where online I can run the numbers without having top pay a machine shop to figure it out for me. Thanks.

The chart I have lists them as 76cc.

Ok thanks, I was hoping for smaller but will still be pushing 10.5:1.

How much piston dome are you using?

.275 I did the math and it will be about 10.22:1