Hi Nick,
In the past, I've used two mediums to store and ship engines. Acid free tissue paper and food grade plastic wrap to keep the paper covering the metal. If you use a mild holding tape (like painter's tape) to hold the tissue, you can cover that with bubble wrap over top of the tissue.
I bought a large roll of cling wrap at my local Costco. The closest shipping supply company I found in a quick scan was Schilling Supply Co. in Rochester. They have different sizes and bundles of acid free packing tissue paper.
Dave