$300 is awfully low for that gun. Assuming the bores are good with adequate wall thickness, the ribs are intact, it is tight and on face, etc., etc., I would venture to say that the gun is well worth $1000 or more.
It appears that the damascus finish is intact and original and the gun has a high amount of original case color. Her friend is apparently trying to take advantage of her. Tell the fiend to take a hike!

"As for me and my house we will shoot Damascus!"