Archrms what are you going to do with the car? Show, Run&Gun, Orginial to spec, or beat the crap out of it every day? Ponds and Genesis are cheaper the a Shelby block and more correct. Shelby block is stronger and better engineered in my opinion. Any of these 3 blocks will work fine for you. How deep is your pocket? IF YOU CAN FIND a 427so block the price will be the same or more an the Genesis or Ponds. It will either be a service block or used with an overbore done to it. 427 motors are thin walled to start .030" over is the safe max on oem blocks. A crate motor may be your answer. If you want to talk on this call me 732-254-3536 after 7:00pm. I am in Jersey.
Rick Lake