It depends on the handle and how it was riveted/pinned, but I wouldn't count on being able to use the same handles again after you take them off. The pins are peened to hold the scales, which would make it hard to get them out. The pin is basically an hourglass shape. The hard part/problem is that no matter which way you push the pin, you're going to push a wide part of the pin (the end) through a part of the scale that has a narrower hole. Honestly, if you want to save the scales that are on it, I wouldn't try and remove them. In all likelihood you'll crack one of them trying to get them off. If it were me, I'd oil the wood if were dry, and leave it alone otherwise. Sharpen the blade, simply remove the surface rust and keep the blade oiled as it is. You aren't going to make it like new, and honestly what's the point? (I know, my opinion). If you want a new knife, get one. If you want to use an old knife, then sharpen it and use it.