Castiel needs an MRI

Castiel is a 3 year old tabby o'love. About a year ago, he started to have a problem walking. We have taken him to the vet multiple times, and ruled out things such as diabetes. His back legs are weak, and he stumbles when he walks. He is also unable to run normally. We have tried acupuncture and itherm, and while this helps for a little while, ultimately the problem returns. We have made the decision to try to get him the MRI, but we cannot afford the bill without some help. The vet is estimating between $2500 and $3500.
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