Right here in OC we have a Home Storage Center where you can buy food in bulk for food storage. It is located in Fountain Valley:
FOUNTAIN VALLEY HOME STORAGE CENTER
17350 Mt. Hermann
Fountain Valley, CA 92708
For an order form, you can download a PDF from Provident Living HERE (you use this to help you sort out what you would like to buy when you get to the center. We recommend you call ahead to make sure they have certain items in stock).
ONLINE THROUGH THE CHURCH
You can also purchase Food Storage Items from the Church through Provident Living, you may access the store HERE