What are safe chew toys?

Hi, I usually order 500g of apple sticks for my chinchilla but I'm worried that he's eventually going to grow bored of them. It's always necessary to have these sticks around since they last longer. Every other toy I've gotten him he destroys after one day; it's beginning to get expensive. I've read on some websites that magnolia trees are safe (prepared), but other websites say otherwise. Is it safe to give him some baked and prepared branches?
Are there any other homemade chew toy ideas?

I've seen others give chinchillas bird and rabbit chew toys, are they safe as well? I'm currently looking at Kaytee Perfect Chews for Rabbits, Bunny Blast Yucca Chew Toy, AUOKER Bunny Chew Toys, BWOGUE Small Animal and Bird Chew Sticks, Sweet Bamboo Chew toys, and Niteangel Natural Wooden Hamster Mouse Tunnel tube. A friend of mine gave me a few timothy hay sticks and my chin loves them, is this a safe treat to give daily?
Thanks