The creamer to use is based on what diet/preference you have. You could use 250ml (just over 1 cup) of either coconut milk, coconut cream, whole milk, quark, Greek yoghurt or even single cream.
In the recipe above we used zero fat Greek Yoghurt. For storage containers, I like something like this, that you can quickly ladle up the soup, put the lid on and then freeze it for later. You can use any mushrooms for this Instant Pot Mushroom Soup. I always go with whatever is the best value for money.