Lloyd,
I have no idea why the action would be olive green, and on a gun this old, who knows what has happened.
I can say this. I've spent the time and money to refinish an old pump one time in my life. It came to me because nobody else on my Father's side of the family wanted it. It was the splintered and rusted wreck of a first year model 12 20 gauge, which, had been a barn gun from at least the 1940s until I got it. I bought a used Italian reproduction stock off of one of the gun boards and a new reproduction of the front wood for it, a big button lefty safety for it (since, the model 12 safety is in the wrong place) and polished it myself. Some of the pits were too deep to polish out. Glen Rock blue hot blued it for slim money. The Winchester buttplate came from a friend who decided his Cooey arms single shot needed a pistol stock. I polished and engine turned the bolt.
Here is the gun.

I HAD to refinish this gun. It simply wasn't usable the way it was. I wish I had taken a picture of it, when I got it. It is pleasant enough to look at, now, and works very well, but, that being said, I wouldn't refinish another pump gun unless it was too rough to use it as it is.
I got this gun for free, got most of the parts used, and that is a good thing, because a refinished pump isn't worth much money. I'd break even, I suppose, if I sold it. I might have $150 into it, total.
The gun works flawlessly. At various times at the range we have tried to get it to act up with 2 3/4" ammunition (it is a 2 1/2 chamber gun) and it simply will not refuse to fire, cycle and do it all over again. I think the choke was opened, since the barrel says "Full" but, measures right at the edge of improved modified.
But, the Winchester people especially, want nothing to do with a refinished gun.
Good luck.
Best,
Ted