I need surgery

Hello, my name is James. I am a desperate owner of a German Shepard, Gracelyn who is 5 y/o. Gracelyn was abandoned as a puppy and was adopted. She is a Bozeman, MT native who enjoys being outside in the mountains, swimming in the Gallatin and Maddison, playing with other dogs at local dog parks and meeting new people. She recently took a nasty fall down some stairs and injured her left rear knee. Dr. Anderson at Baxter creek examined her and explained she has the K-9 equivalent of a torn ACL. I was referred to Dr. Jackson at Bridger Veterinary Specialists who informed me the total cost would be approximately $6500.00. I work in the mental health field with underserved populations and do not have the financial means to get Gracelyn her required surgery. Any help anyone can offer would be greatly appreciated!