First time I read about the link between Gritzner and Kenmore (White) was
this blog, a Kenmore 117.841. I have actually seen a few Gritzners, and
here is a German blog with pictures of what probably is the origin of this model (...there are always predecessors as far as origins go, it goes on an on lol). According to the first blog; Gritzner was bought up by Pfaff and look at Pfaff 139 and 239. When googeling for example pictures, I bumped in to yet a blog, and
this guy has done some work on this already.