Midsouth is having a very good sale on their Lawrence #5 and #6 chilled lead shot (2% antimony)... $30.23 per 25lb bag. I have melted down this shot before and it cast very good. Lots of graphite must be skimmed off though.

That's $1.21 per pound...much cheaper than Roto metals

https://www.midsouthshooterssupply.com/item/00137chsh6/lawrence-chilled-lead-number-6-shot-25-lbs