Affordable Pet Surgery for TPLO?

Where can I get affordable surgery for my dog? She needs TPLO on her left rear knee and our vet wants almost $3,800, with x-rays, surgery, and medications. She is almost 3 years old, a Staffordshire Terrier mix, and weighs about 57 lbs. We can't afford that much, and we filed bankruptcy so we can't apply for any type of credit. My wife has been out of work for over 4 years and is now on disability.