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They make full on 3d scanners but most parts do not need "3d scanning" so much as they need a few minutes in the hand of someone with a caliper and a sketch pad.

The field of photogrammetry deals with taking multiple photos of something to create a 3d model. There is free software for consumers that can do this. But there are a lot of limitations and currently the traditional way of making a CAD model more or less by hand is almost always faster/cheaper and more accurate.

Never did it, but in Windows 10 you can is Kinect to 3d scan an item, it's on the Todo project list...

There are a few services including Autodesk ReCap which you can give a number of high quality photos and a 3D model will be produced which you can then scale appropriately in your CAD software

For most things scanning works pretty poorly. IME, you are better off you use some calipers and a free to use tool like Fusion 360 or TinkerCAD, or a really free tool like OpenSCAD to generate the model.