Looking for a pair of 66-67 273 Heads

Since I am rebuilding a 67 Commando, I'm hoping to find the closed chamber heads that came on the engine. I truly appreciate you taking the time to go through the heads you have available for sale. If I'm unable to locate a set of 920 heads, then I will most likely pick up a set of open chamber heads that you have available. Thank you again and Happy 4th of July.