I had one like that. Back in the 70s (man weren't those great years?) Bill Jordan advocated round butt 19 w/four inch barrel. I sent two 19s to Smith to swap the barrels. (Four inch and 2.5 inch, respectively.)
I didn't like them because the barrel ribs didn't line up, so I reversed it.
That gun in your link looks like mine.
"I say, boy, I say, you're doing a lot of choppin', but no chips are flyin'."