That serial number puts it in the 1955-56 range.
I have a pre-43 also, serial # 5XXX, which puts it in 1954. I also have a 34-1, and the weight difference between the two is amazing when you can compare them side by side.
Very nice guns, as are all SW revolvers IMO. I would imaging re-bluing an aluminum frame may be more difficult and more expensive. Your wife's gun is indeed a shooter, and I would leave it that way if it were mine.
One thing to consider though is to get a cheap set of grips to put on it and save the original ones. They look to be in much better condition than the rest of the gun. Those diamond grips are getting more valuable every day!