I deleted it after deciding it was off topic .
I suggested a 540-565 BBC based on EAGLE OR OHIO parts and a merlin or Dart block. 700-800 HP RANGE EASY for 10-12 k.Buy box stock heads from any of the good manufacturers and buy all the parts from a jegs catalog.
No Fancy high maintenance valve train. A big HP small block is very cool but they are more sophisticated and require more maintenance and know how.
any decent gearhead can maintain and tune an engine like I described