Hard to say if your barrels have been reblued at some point. The streak in pic #2 could have been there all along, and just became more evident as the barrel bluing thinned and wore over time.
I agree completely with Dustin on the need for proper barrel prep, should you decide to reblue them. With this gun, I think it would not hurt the value one bit. It would probably enhance the value. Cerrakote would be a great way to lower the value. So now you need to find someone who can do it right, and your new concerns are shipping both ways without loss or damage.
