I generally buy from the junk yard. I get plumber's lead most of the time. Once, I hit the jackpot and got 24 ingots of Lyman alloy for junk price.
Wheel weights are not lead, any more. I got the last bucket from OK Tires over a year ago.
Armed and Safe: Not just a theory
If it time to bury them, it is time to dig them up.
Remember, "Behind every blade of grass."