I owned a 7-shot 619 the first year (2005) they were produced. 4" barrel on mine. No other lengths were offered at that time. I checked before purchasing that model.
That L-framed gun looked like a K-frame Model 65 (my favorite .357) on steroids, which was the only reason I bought it (despite the inclusion of the lock). Good gun, but I eventually traded it off. One of the only Smith post-lock models I've ever owned.
It would have made little sense for S&W to have offered longer barrel lengths... as it was a model with bull barrel &
fixed sights. A duty format gun rather than a hunting or target weapon. Like this one: