If it is S&W law enforcement ammo, it is most like the standard ammo made by many manufacturers. Otherwise, their standard ammo was loaded to a level slightly hotter than the norm for the times to use for hunting though some was sold to law enforcement as a "penetrator" round. Cor-bon would be a good source of similar ammo as would Buffalo Bore, Garrett, and numerous other specialty manufactures. This ammo is more like over 30 years old as I believe S&W got out of the ammo business in the late 1970s. This was the older "Super-Vel" line of ammo that kind of revolutionized law enforcement ammo by using lighter, often hollow point, bullets at higher velocities. Alcan was a common supplier of components but I don't recall who they were associated with. They were definitely not an "oddball" company.
Starting in the mid-1950s, 357 mag ammo has been down loaded for use in the smaller K-frame sized revolvers which became popular for law enforcement use. The original loadings meant for the larger N-frames had a tendency to batter the smaller frames to death plus they were rather hard to control and over penetrated for law enforcement use.
I feel ammo today is much "better" than that of days gone by; there has been a lot of research and development that has lead to very good and dependable ammunition. The difficulty lies with the consumer, one needs to look closely and carefully at the ammo specifications to get what one wants. The 357 mag is the most difficult as it bridges two vastly different areas of ammo requirements.