i'm not in LI but here is what is important to whomever will do it.
How many molds are you getting made?
How many cavities per mold?
A large grub is usually thick and takes a while to cool enough to be de-molded.
Basically it may take a lot of time to make theses. Possibly only eight or less baits per hour, depending on how the above questions are answered.
So time + materials and electricity/heating may cost you a couple bucks per bait.