I have a habit of asking people I don't know "have lead?", and someone I don't know from a different department at work said "yes, and you can have it - I'll bring it tomorrow". He showed up with this 50 lb slab. I propped it up with wood working clamps and each hole took a couple of minutes, since Wally World only had propane rather than Mapp gas today, but eventually it was in Lodge Pot size chunks, and is now in the shape of Lee ingots.
I hoped it might be pure as it seemed to scratch easily, but my Lee tester says it's 11.8 BHN. I am not complaining though - say, you wouldn't have a sailboat keel that you want to get rid of, would you?