The Model 1950 .44 Special which became the Model 21 would probably interest you the most. In more recent times there were small production runs of fixed sight Model 29s and 629s. There was also the weird Performance Center Models 625-10 and -11 .45 ACPs. They had super short cylinders that made their 2.1" barrels barely stick out of their frames. While they only have over size fixed sights installed in frames machined for adjustable sights there was the Night Guard series. They included the Model 327 .357 Mag., Model 310 10 mm, Model 357(?) .41 Mag., Model 329 .44 Mag. and Model 325 .45 ACP. The Model 21 is the only one I thought of that is the correct vintage for this sub-forum.

I like the way the lack of an extractor rod shroud makes the Model 58 look like a more serious Model 10.