Well you have a couple of ways to find it.

You could measure the diameter and depth if it is a cylindrical shape with a flat bottom. I'll calculate the cc with that data.

Or you could use the Mopar method divised for Hemis where you put the piston some precise distance down, seal up the ring area, and cc the block. Subtract the volume of the cylinder and you have ccs of the dish.

You could even set the piston up level and just cc the dish. That's probably the quickest method.

I'm surprised JohnRR hasn't answered this post, maybe it's beneath him to talk about 2-barrel engines? He knows more about stock 383 pistons than about anyone else here.

R.