Turbo small block

I have a 74 dart swinger with a 318. I am going to do a engine swap with a turbo conversion my question is what will be the best base engine my choices at 360 la, 5.9 mag, or 5.7 Hemi. My biggest concern is block strength. I want to be able run it hard without worrying about cracking the block. I am doing forged internals and a fuel injection. My second concern is throttle response.