Recently bought this accordion from an auction, can someone help me identify it?

[sonofmeh]

The front reads "Paolo Soprani" and "Glorioso," but the iconic Paolo Soprani logo is not present anywhere on the instrument. In case it's important and hard to read, the sound settings are Fagotto, Saxofono, Concert, Organo, Violonc, Violino, and Flauto. The case is lined with red but unmarked. It came with a book titled the "Sedlon Accordion Method" which looks to be published sometime in the 1950s because whoever had previously owned the book had written dates into the pages, the earliest of which was in 1955. Additionally, a Paolo Soprani advertisement of sorts was tucked inside the book. If anyone knows what exactly I have or if I can find a serial number on it somewhere, that'd be great.

 

[JIM D.]

A 4/5 reed mid 40s to early 50s top of the line model.
This one should have hand made reeds.
As for as Ser. # , many Italian imports were shipped without one, as the importer would then apply one of their own. As for the shift markings - they were for the at the time European market. In the mid 50s most imports were shipped with what we now call common markings.
https://en.wikipedia.org/wiki/Accordion_reed_ranks_and_switches

 

[triskel]

There are several models with similar grille patterns to this one in Paolo Sopranis 1953 catalogue, the most-similar being this Italian-model chromatic (right):

http://i17.photobucket.com/albums/b66/StephenChambers/scan0006.jpg>

Though the grille construction and the couplers are more like this Scandinavian-model chromatic (left):

http://i17.photobucket.com/albums/b66/StephenChambers/Accordions/scan0001.jpg>

But the only piano accordion listed thats of the same specification is the 4-voice, 120-bass Lusso, and Id suspect the OPs one may well be the next version of that model (about 1953-54), after this one (below right):

.http://i17.photobucket.com/albums/b66/StephenChambers/scan0005.jpg>