Eggs - My fiance and I always get the huge 36 pack. Granted they are not pastured but if you eat a lot of them it's a great deal.
Chicken - Again, not pastured but you can get organic (although that's really just a buzz word since there are so many loopholes).
Salmon - Lots of selection here from frozen to "fresh", wild-caught, etc.
Nuts - All kinds of nuts! Almonds, cashews, walnuts...
Protein Powder - You're not going to find "paleo protein powder" but there are some decent choices (Cytosport Vanilla is my favorite) if you allow yourself to have it now and then.
Chicken Sausage - I think it's the Casual Gourmet brand that I usually get and all of the ingredients listed are paleo.
Romaine Lettuce/Kale/Spinach - Only if you plan on eating LOTS of greens before it goes bad.
Cheese - Not necessarily paleo but they have some fantastic cheese in bulk.
Jimmy Dean Turkey Sausage - Great to go with your eggs for breakfast.
Bacon - The Costco by me has Niman Ranch which is really good.
Bison Dogs - Just picked some of these up the other day so I'm not sure what they taste like but they look good (no additives)!