As most of us birdy folks I get a lot of nifty things at the Dollar Stores. A few weeks ago I was in our local one in Clarinda and I saw these one piece plastic potty chairs for toddlers. they come in shapes like hippos for a whole dollar!!!
Put it in the bottom of the cage and store their footie toys in it.
Another toy box that lasts longer is to get a small igloo lunch box, drill two holes it one side. Use screws and metal brackets to fasten to the side of the cage bars. These hold up even under Too beaks and can be used for quite a while, and clean easily.
Nan