I have dealt with a gentleman in the Scranton/Wilkes Barre area. He is most professional in his shot making.
He does 50/50 for 'prepared lead' (i.e., ingots) - I forget if it is 60/40 or 70/30 for 'raw lead.'
There is much more work in the prep of the ingots than there is in the manufacturing of the shot (once the shot maker is set up and running correctly). Quite honestly 100 pounds of lead is nothing.
The first time I tried his shot I sent him a large USPS priority mail box filled with wheel weights ~ 75 pounds of lead (I had selected large ones and I had culled all the 'crud' from them as well) - I got back one bag of shot. After that I provided him with prepared ingots - typically 250 ~ 500 pounds at a time, and I got back 50% as shot.