Given the fact that the sign is a neon light construction, it's not so easy to find an actual digital font corresponding to the original design. The "NFL" looks probably custom/deformed and the "N" of "MAN" looks 180 degrees rotated.

You can try to approximate it by modifying a similar font e.g. Rita Smith (Medium) by Claude Pelletier

It is the old NFL logo font (pre 1980) Any ideas?

There was no "old NFL logo font", just part of a designed logo. There are some fonts such as the one Fivos suggested, that could be deformed to match. In all likelihood, you'll never find a font with an "N" like that, with one oval serif and one rounded triangular serif.