A couple of comments: (OK, probably more than a couple) The mold putty can be a pain in the ass to get right, but it can be done, as long as you don't expect professional results right off the bat. The tin with the yellow tail in the pictures is my first attempt at molding from scratch, and after wrecking the first mold (as I expected to do LOL) the second one came out OK. The learning curve is pretty steep, since pouring with rubber molds is a lot different than using aluminum; it took me three days to pour a fishable jig, but I'm getting the hang of it in small steps. I make my masters from Sculpey III and give them a few coats of acrylic to smooth out the surface. The results aren't good enough to sell (yet) but they're plenty good enough to fish. The tin in the pic is three and a half ounces and it swims great. I'm going to try pourable silicone once I run out of mold putty; I think it's probably better suited for getting good detail, something that's tough to get with the putty. I've worked up a lot of designs over the winter, and I'll probably hunt up somebody to make some aluminum molds when I decide which ones I like the best. BTW, I use pure tin - my wife's studio loft is on the second floor of the garage, and she doesn't want any lead smelting going on downstairs. Neither do I, come to think of it. Besides, tin is really something to see in the water.
The Do-it flutter jig in the picture is also tin - the trick to pouring these little beauties is (aside from making sure the metal is good and hot) is to heat up the through-wires before you put them in the mold, which should also be as hot as you can get it. I use a Hot Pot 2, and I just lay the wires on the metal stand while the tin melts, and they're ready to go when the metal is. Pouring metal is a lot of fun, but it does take practice.