When the tire comes off you’ll be riding on a plastic spoke. In all probability you’ll need a complete wheel replacement; this is not like a bicycle’s construction. If you are going on a 1or 2 day trip I wouldn’t worry about it. Longer and I’d order a new part from
Amazon.
For comparison, I used my wheelchair for one week while waiting for a repair.
Just to note: your chair is better made than then one ordered for me by rehab. Mine has no s/s metal parts.