Nontoxic alternatives

[Mr. 16 gauge]

Anyone here hunt ducks with a muzzleloader? I've been planning on hunting them with my 62 cal. Trade musket; now I find out that the fellow who invented bismuth shot died and his family has closed the factory and it is up for sale....and there are no takers. The only other alternatives that I can think of are tungsten matrix, which isn't offered as a loading component, and ecotungsten, which is relatively new....the company claims you can use it in lead recipes, but I am a little leery without any pressure testing data. It is also very new and quite expensive.
Anyone know of any other nontox in development that might be usable in my flintlock?
FWIW, I probably have enough bismuth to get me through a season or two.