The serial number is from an N frame from about 1956; no way it was original from a K frame of the 1980s. The finish looks odd and the stocks look slightly proud at the bottom of the grip frame as well, so I suspect the original SN was milled off and a new one stamped if the photo is of the model 17-6 in question. If this is not a late April Fool's prank
.
Is there an SN in the yoke cutout? It appears there is one in your second photo but I can't make it out.