Originally posted by boriscleto there are at least 2 different versions. Most Sears SLRs were rebadged Ricohs, but the KSX-P was a rebadged Chinon. The lens I have was the kit lens for that camera. Look for the Auto Chinon 50/1.7 k-mount in the database.
I have both. The Chinon seems superior, though my copy was beat to hell before I acquired it. They're easy enough to tell apart.
The Chinon is on top (white print), the Ricoh on the bottom (red print). The biggest cosmetic difference is the filter size is smaller on the Chinon at 49mm. The Chinon is slightly larger though in profile, but has a shorter minimal throw distance.
And a side view.
The Chinon also has slightly more curved blades, though I can't say how that effects the bokeh to be honest as I've never really tested them out head to head beyond a few test shots.
Chinon is on the right here.