This ^^ I am not an expert, but I am sure the compression is going to come in right around 9.5-9.8. but if my dads cam is still well suited and is accessible right now, why not go with that and not have to wait.
The only way to actually know for sure your actual compression ratio, especially considering the shape and style of that piston is to do a .500 down fill on a cylinder and then you will know exactly what the dome volume is and not be guessing at it.