This appears to be a new-old-stock set and includes the gold-embossed US leather case and all paperwork as shown. The box and leather case has some "shelf wear" from being around 60 years old but the slide rule appears to be mint and unused and includes the extra plastic data strip insert that is often missing from these sets.  

See:  https://americanhistory.si.edu/collections/nmah_1214520

For additional information about this model.