The M1 is closest in function and looks. As far as I know the newer M2 Benelli and the M1 are the same from a functioning standpoint. Just a different stock design on the M2.
The choke tubes would interchange on the ones I had, but I doubt anything else will. They function on the same principle, but they are designed a lot differently. The recoil spring on the Benelli is in the buttstock and in the foreend on the Stoeger. The Benelli has a shorter 3+1 mag, where the Stoeger is longer and is 4+1. The foreends are different lengths because of this.