The cereals can be bits and pieces of any you have leftover. We have found that we like the variety in texture that a crunchy rice cereal gives along with the chewy raw oats.
The oil can be whatever variety you prefer. The coconut oil adds great taste and is known to be a fat burner.
The flax seeds can easily be omitted. We use them due to their good fats and fiber.
If you don't have chocolate chips or cacao nibs then what about breaking up that leftover