Tom, I know what you mean! I messed with making some molds years ago, with plaster of Paris, and RTV silicone.
I've bought some one of a kind, used molds, and have had to make wire forms for them. It's time consuming, and they don't always turn out so they fit great.
I looked into having the wire forms made too and the minimal order size & cost, didn't justify spending that kind of money.
If I was going to have such a mold made, I would start with an existing and popular wire form, so they're readily available and easy to obtain.
But very often when someone asks about a mold for a commercially produced lure, like is shown here, they don't consider that the molds probably not available, and even if it is the wire forms may not be.
IMO, it's fine to make a RTV mold for limited use too, but they have a limited life span compared to a machined aluminum mold, so can depend on how many lures are wanted. It makes little sense to make or have a mold made, if all they want is 20 lures as an example.
I just ordered 3 new molds, all CNC cut and the cost was almost $500, which even then isn't a great amount for a business, but I wouldn't have done it if I only made lures for myself. It's cheaper to buy the lures.
