Hi Chuck, and welcome!

Let's see

:
Sequinned lettering = old.
Severely angled corners = old.
Narrow black keys = old.
Grille pattern = old.
Relatively "short " bellows corners = old.
80 bass, 34 treble keys = likely 3 sets of treble reeds.
Are there any knobby looking brass or chrome metal switches along the back of the treble keyboard?
Was your mother's name by any chance "Aida"? If not, that's possibly the name of the model of the accordion.
How old?
Definitely more than 60 years.
My guess is, it's from the 1930s ( but could even be from the late 1920s)

.
"Sternberg" may be the maker (or distributor

).
Cosmetic shape is pretty good for age.

One white key has lost its top.
Probably there's a few loose reeds and leather valves rattling around inside of the bellows?

Theoretically, everything is fixable: it only requires (quite a bit of) money and access to a good technician.

See here: