Assuming your crafts are high enough to craft ingredients needed, here is this items true cost:
1 x Silver Ingot: Ores are bought from NPC and crafted so only cost is around 1500 gil per ingot
1 x Insect Wing: Insect wings are farmed from bees, beetles, and flies.
True cost: 1500 gil
Any ingredients that are NPC sold for less than 100 gil will be considered no cost.