Wheel weights can sometimes be gotten cheaper than pure, and I keep them separate. The WW does well over 1/16 but the smaller ones do best with pure. Any scrap lead should be in the pot when first fired up to slowly warm it and help in removing any trapped moisture. Moisture can cause violent reactions as happened to Jungle Jim a few years back. I'm a scrounge and don't pour that much so I have no trouble keeping enough for my needs. I have never had the need to buy pure but around here folks buy from the scrap yard for about a dollar a pound, when they have a mind to sell to you.
Creativity is just intelligence fooling around