Alchemy, enchantment and necromancer materials can be used from the coffer. AFAIK your necromancer should have access to any body parts in the coffer, but I kept a list handy of the best parts I had, and sold anything that wasn't an upgrade. If there are any parts in your coffer after going into the creature creation screen, check that they are not duplicates of ones you already have.
There are a dozen alchemy ingredients you can send a runner for, 8 minerals and 16 gems. If there was a single enchantment runner, it would take longer to get the required ingredients.
Besides, what would Dick and Harry be without Tom?