It is Swiss.
Bellinzona is a beautiful town in the southern part of the country.
Your are correct for the Swiss origin and the year 43. From the end of 1800 until around the 1970, many articles from the Swiss army were made by private companies all over the country. Bellinzone is the “capital” of the italian part of Switzerland. Each pouch contain 2 clips of 6 ctgs. It is a commun piece.
I have one somewhere which is much the same - indeed Swiss. I still see them at gun shows.