I use a vise instead of a hammer. Get everything lined up close the mold against the hook, put it in the bench vise and put on the pressure until you have an indentation. I've done it dozens of times and not one oops.
My biggest problem is throwing the bait and only getting the blade back unless the gap is completely closed. I lost a few then switched to split rings.
I believe you would have to go to a manufacturer to get what you want. I'm only guessing but they are probably overseas some place. I heard at one time living rubber was manufactured in Vietnam.
The wire I use is copper and came out of an electric motor from my table saw. If I ever get it all used up a have another motor on a shelf waiting to take over.
It will be a good time. There is so much to learn and you will never learn it all. I have about 8 guys who come over and make baits in my garage. They range in age from 15 to 76 and we are all learning every time we make baits.
The first thing I'd recommend it read the don'ts for newbies above your post. I think you will have to look at a bunch of sources to get all the things you will need. If you spend some time looking at topics on this forum you can get a pretty good idea of options and sources. Just don't think that you will save any money for the first several years and maybe never.
No just oil from the kitchen. I keep a small bottle of it on the work bench at all times. When a rod needs some slickum I just dip the tip in the oil and go.
I used to completely fashion mine and have had the wires all different lengths but I found a guy who has some incredible wire harnesses so I bought 40 from him and use them. They are probably 6" long but I have never actually measured them. I use willow and Colorado blades in size 3. I put blades on all the wires except the middle one. I only run 3 baits.
When you pour with the divided cup, hold it about 6" above the mold and let the tiniest stream flow out (smaller than a toothpick if you can). That will let the colors mix better.