Hello, I'm sure that on Melodeon.net you can find more information about the accordion, those Paolo soprani usually have many admirers in traditional Irish music, they normally use them in B/C or C#/D. The antiquity is usually discovered by the color of the shield, the shape of the grill and the typography being blue, red, black from oldest to most modern, the most sought after from what I have read are those with the blue shield. Below I copy and paste from Melodeón.net something that I found when I was trying to find the manufacturing date of mine (I have one with the red shield). :
Basic rules: (correct me if I'm wrong)
All years are approx.
1900-1920 Wooden box with open keyboard.
1920's 1930's- wooden box with small buttons, some bare wood, some painted crazy colours
1930's - start of plastic covered cabinet. Large logo either in writing or inlaid in stones. Small buttons.
1940's early 50's- famous greys. Small buttons, the well known small logo, and aluminium grill
mid 50's - about 1960 - red boxes with blue badge
1960's - red boxes with red badge and small lettering "paolo soprani"
1970's - larger lettering of "paolo soprani"
1980's - the end of the "real" paolos, large italic lettering, after mid 80's the boxes were made by bafetti, same name, different instrument.
2000's - jubilee came along.
Hope this can help you. greetings