we have a nextengine scanner at work, its not as easy to stitch the scans together as the manufacturer makes out but is still a nice bit of kit for the low cost. 3d printers are hell of expensive, but teamed up with a scanner you can reverse engineer to remake all sorts of stuff
the 3d printers are usually plastics/resins or powder and binder based, to make metal parts you'd make a cast, or the scan can be used on cnc machines to make the part.