Emergency vet bill

My kids cat has been missing for a few days. Yesterday I put up a Facebook post and today the cat was returned to my door step. She had been hit by a car and can't walk. Just an emergency visit and x-rays will cost $500. This does not include any procedures or pain medication. I have tried to see if the vet will work with me on a payment plan and unfortunately they do not do this anymore. I've called many places some are not taking new clients at this time nor do they offer any payment plans. She just turned 6 months old and I'm trying to get her the care she needs but hit a financial hardship right at this moment.