Jeff,

In the posted logo there are two parts - the NCL dragged with tails and at the bottom it reads American Favorite Cruise Line.

The logo is a combination of the logo by itself from the time NCL bought the Norway as shown in the postcard in the link you provided, the line American Favorite Cruise Line was added I think if I am right as soon as the Project America and other America cruise ship was/were introduced into the fleet. Which at that time they rebranded it to Norwegian Caribbean Lines.

We can narrow the search to this timeline -mid 60's to late 60's. Within this time frame so many changes in the NCL.

What is your thought?