I was paying $20 per pail when they were mostly lead ww, now with the zinc volume very much increased I have been paying $10...and getting no argument from my supplier (he's not a big volume supplier, prob average 2 pail a year).
Y2, if your looking to increase you financial gain in the WW bidness I think you will have to sort the zinc out, melt & clean/flux & cast into ingots to realize any significant $ increase.
an edit to add to the above; after a bit of research & personal experience : an old time 5 gal pail of WW will av. 150#- releasing 100-110# of ingot lead...a modern 135# zinc infected pail will yield 80-90 # of lead. A good melting system with a couple of muffin tins that easilly dump when they should will render a pail of WW into ingots in 2 hrs easily. Even with 3 hrs handling/melting time included it and selling the refined ingots for $1.50 per lb. would realize a somewhat good return on time.