For what it's worth, back in the 80s there were quite a few unfinished Parker barrels around. They had no marking as to type of steel, just the unfinished weight
stamped on the flats. I have no idea where they originated from but would assume they came from Remington. They were very raw, unchoked with lots of cleanup of solder.

I learn something every day, and a lot of times it's that what I learned the day before was wrong