Lead is currently selling for about 95 cents a lb. You would probably have to buy at least a ton to get that price. So somewhere between that and 1.25 a lb would be a good number depending on how much you need.
Go to the "Greatful Lead Sinker Company" out of Florida I think. They are on the web. You will never pour your own again. All types and sizes for about $3.20 lb delivered to your house. No more lead fumes for me.