273 needs new heads, suggestions

EmersonC,
See the Mopar Tech archive forum, Engine Casting Numbers thread and the Cylinder Head Casting Numbers thread. From the casting numbers that you gave, you have a '64-'66 LA 273 engine and the heads were from a '67 318 with 1.78 intake and 1.50 exhaust. Those casting number threads are very helpful for identifying parts.
Richard Sweet