Metal Pan Replacement Help!

I'm looking to replace all of the 4 plastic pans in my Critter Nation with the metal pans ASAP. I'm looking at Bass but only see the bottom level and the middle level (with the cut=out). I need both of those but also need to find metal pans for the 2 smaller shelves. Where did others get theirs? And do they fit the shelf in the critter nation correctly? Any help would be appreciated!! Looking to do this ASAP. Thanks!