Welcome
You've come to the right place! :welcome:
You can still use your cage, it just needs a few adjustments. Check out housing and supplies for a a lot of really cool ideas for cage decor. If your chinnie likes the tubes (my did in the old cage, but I traded out the plastic) you can get PVC pipes (6" diameter is probably the best) and cover it in fleece to help prevent chewing. There are some for sale by some of the vendors in the Classifieds if you don't have the ability to make them yourself but if you do there is a "How To" in the housing section just like the hammocks and shelves.
There is also such a thing as a metal guard for your water bottle if you don't want to buy a new one. Your pet store may have it but sometimes you have to get creative when seeking chin proof items. For example, I (and it seems many others) really like the "coop scoop cup" that you find in the bird section, plus a lot of the wood over there is chin friendly (not the rope or plastic though) like the coconut, palm shredders, and the wooden perches like manzanita or grapevine.
Fleece is the most chin-friendly material because it doesn't have any threads for them to chew and swallow which can lead to intestinal problems like blockage. There is a "mini sale" of fleece items from a recent show
here. I'd check and see if she has any left.
For treats, if you really feel the need to give them, try plain cheerios, shredded wheat, rosehips or just new and exciting pieces of wood. Chinnies really love apple bark and you can never give too much wood not matter how hard you try.
Plus it keeps their teeth filed down and keeps them healthy and happy. I know that I also like to just hand feed my boys food or hay (which seems to be their favourite treat no matter what I try, honestly. Riku is completely uninterested in pretty much any wood or rosehip I give him but LOVES when I feed him hay!)
I hope that helps out. I echo others that supporting the sellers on here is a cheaper alternative to your pet store, plus you don't have to worry about if it's actually safe for your chinnie. A lot of pet store items are marketed to chins, but have a lot of "junk food" in them. Like the dandelion drops whose main ingredient is sugar and the food that is full of dried fruit and nuts which their tummies can't process well. Those kinds of foods are probably why pet stores think chinnies only live 6-10yrs. I'm shooting for a full 20 personally