don't use the teflon, it will come off and you'll have a mess.
stay away from alum pots as they WILL fail and then you'll have a big mess.
stainless, may be ok. hold off get a small cast iron pot.
you'll need a LOT and I mean a LOT of heat if you are expecting to melt 40lbs of alloy or more at once. a one or two quart cast iron will do nicely. Something with a lid works better.
Make sure where ever you set up is sturdy enough to handle it. Meaning it won't sudddenly or slowly tip over. I would also advise you to get gloves, apron, goggles and a good dipper oh yea, and something to scrap the slag off the top and an old metal coffee can to put it. Collect as many ingot moulds as you can, once the lead is poured and sets up it's still 400 degrees hot. You'll not likely be handling them any time soon. An old sheet of plywood is a good place to dump the hot ingots so you can refill your moulds. You're not going to muscle a 40lb pot of lead at 600 degrees to pour into one pound ingots without disaster.
