Restoring a WW2 USA paratrooper flashlight?

I got this lightfor $10. It has an elbow at the top so the light shines off to one side instead of being a strait toob. It's compleatly made of steel and is really rusty on the inside. I don't have the equipment to remove the rust and even if I did I would be really worried about ruining the inside. Is there anybody I can take the light to who might fix it? On the elbow there is a circle with TL-122-A on the side. Off the back there is a thing so it can be mounted on your pocket. The base has a ring like thig that pops out that I asume is for runing your belt through. It also has

refill with SLALIGHT batteries

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USAlight

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made in USA U.S. Electric

MFC. Corp

The switch is made of brass and there is a button above it as was comon for design back then. The problem I am having is it won't work. The bulb is fine I placed it in a diferent flashlight and the thing lit up without me using the switch at all. When I did it just stayed on. When I placed new batteries into this light though I could not get it to light at all. No matter where of the 3 positions the switch was in it just won't work. It was a little seized when I first got it and had to play with the switch for some time before it was where it needed to be so I know it was very rusty right there.