And HERE is the stamp that marked them. And the engineering drawing for the stamp dated 1989.
This is a Remington stamp. Made for when they intended to start making Parkers again in the late 80s.
My guess is that these barrels were made by remington at that time and later fitted to a repro as an extra set of barrels. And serial numbered as such.
20375DA2-94C7-4E0E-BB7D-0BB6A45B2043.jpg