Wow, 3200 newer than the one sitting next to me...and dang that has seen some abuse.
It's interesting that it's cut for a drum mag. That could be fun once you spruce it up. Greatguns has a folding adapter that might help restore the rest of the stock, and allow for an M4 style buttstock.
Seriously...get a Frontier Big 45 scouring pad for less than ten bucks shipped, usually within 3 days no less...and attack that thing with it. You might not even have to reblue much. It will remove all the surface rust, and not affect the bluing whatsoever. If anything, i will blow your mind enough to always use it. I even use it for removing cosmoline, it's shreds right through it, and you can just shake it in the mineral spirits bucket clean.
You can also cut off a bit of it and use it in your bore instead of a patch, or even with it on a patch pusher chucked into a drill. This is great for getting impacted lacquer out of your chamber too.