273 Commando Engine Clone

I own a 65 Barracuda that had a 273 commando engine. I very stupidly pulled that motor and sold it 2 years ago. I am now regretting my decision of selling the commando engine. I have had no luck online locating another commando engine. I was curious about buying a base 273 engine and building it into a commando clone. What was different on the 2bbl 273 and the 4bbl commando engines (obviously the carb, valve covers, air cleaner, and intake)?