I looked a bit for the model. It seems it is a sort of "Sudent Pen" with a nib style called "Stylpoint".
Here's a link to the Penhero article featuring the Sheaffer Imperials. The 1'st GEN. nib is the same as your mom's Sheaffer. Only they were touchdowns...
PenHero link
Responses
www.newpentrace.net