Thank you for posting the additional pictures. The CT., U.S.A. in the rib legend means 1919 or later and the fact that there is no PARKER BROS. OVERLOAD PROVED stamps on the barrel flats --
172320 02 PARKER BROS. OVERLOAD PROVED.jpg
means the new barrels are from before 1926. I have a gun that got a set of barrels in that same time frame and unfortunately there were no surviving records to confirm the installation. My barrels have a number stamped on the left barrel flat --
56213 11 153 Annotated.jpg
Is there a number in that location on your barrels?