AFAIK the Italian/Beretta choke marking system of stars/asteriks has never changed.
Pre-war guns are marked the same as modern. The only changes has been the addition of choke tubes and sleeves and a color system marking on some of the sleeves. Some tubes use hash marks but they copy the stars as far as number and what choke they stand for.
..and the traditional open choke bbl on an O/U is the bottom bbl. The tighter choked bbl on the top. Same as most SxS's are choked open in the rt bbl and tighter in the left.
There are exceptions of course. Certain hunting and some clay target guns were made with 'opposite' choke bbls.
But that is mostly irrelevant now with interchangeable choke tubes. You set it up any way you want.
Here's Beretta's rather lengthy current choke explanation options.
Scroll down to the bottom and they list the original fixed choke markings (stars) and their equiv. in 'Merican choke marking.
beretta choke tubes identification suggestions
Some of the Beretta BL series were marked with US style choke markings (Full/Mod,,ect) as imported into the USA in the 50's, 60's and 70's.
I think J.L.Galef was the primary US importer then and had them do that for their imports.
The BL4 bbl'd actions we used at Pedersen Custom in the early 70's were still marked using the star system. But they came to us in the white from Italy and with no other markings on them other than proof marks,,not even a Beretta name.