Something like this in a standard drill. Any scratches in the lead can easily be smoothed with sandpaper..................
http://www.screwfix.com/p/surface-preparation-wheel-with-arbor-100mm/31074
...or... a few coats of paint stripper, and some scraping.
When the lead is restored and cleaned up, do finish it with "patination oil". Just rub some in with a piece of rag. It stops the lead from oxidising and looking dull and tatty.
http://www.amazon.co.uk/Bond-It-Patination-oil-flashing-oxidation/dp/B006VBYM06