Sigfried Rentzschke engraved for Smith & Wesson for a couple of years in the late 1950s before going independent. He did a lot of work for Winchester from his home in Massachusetts. I was contacted by his neighbor several years ago about a 44 Magnum I was researching and he arranged for Mr. Rentzschke to look at photos of the gun. If I can find his contact information, I will send it to you.
Bill
Bill