Nuts? Dried berries (cranberry cherry blueberry raisin). Dried apple or mango. Foraging Herbs for small animals (like hay, chamomile, rose, etc sold in small animal section).
Other non edible things to chew and throw around like paper towel rolls, wine corks, anise stars, colored plastic milk or juice caps, balls, trinkets from old bird toys? Sola balls, wood chunks, cardboard chunks, mahogany pods.
my birds have a toybox or extra food dish filled with fun things to chew and manipulate.
Jasper particularly liked to chew the soft wood, Sola, cardboard, cardboard bagels, coconut husk rings. Willow likes to play with toys woven from palm leaf and little gadgets and chains.