Help my service dog walk again

Heya. I'm Magda and this is my boy Gucci. Gucci is a 3 year old American Bully. Happy, loving, friendly gentle giant. I've had him since he was a 12 week old puppy. We've both been through a lot together. He is my rock, best friend, my cardiac alert dog and the No.1 reason why I am still mobile and independent. He was just a little baby while coming to visit me in hospital when I was battling for my life after botched heart surgery. He was with me when I was recovering from 2nd heart surgery after which I lost use of my left, dominant arm. He learnt how to recognise subtle signs of my heart malfunctions and to alert me, so I have time to sit down before I pass out. He was there when I was diagnosed with advance, progressive, multisystemic neurological illness. I was told I'd be soon bedridden, but we both didn't give up, and 2.5 years later, I'm still mobile enough to take care of him and myself. He is there for me every time my PTSD (connected to my near death experience after significant cardiac incident) kicks in. He calms me down when I panic, he wakes me up when I have nightmares reliving my death. He is here for me on good and bad days. Now that he needs me, I can't help him because I don't have money...

Gucci injured his hind leg in November. It resulted in seizure and a mini stroke (probably from wee blood clot travelling from his leg to his brain). The vet advised 8 weeks of rest and anti-inflammatory meds. I did physio with him, and within a month he didn't have any signs left of that mini stroke. Unfortunately, despite months on strict rest and meds nothing was changing with his hind leg. We did an x-ray that proved our worst nightmares - his cruciate ligament was torn!

Gucci desperately needs surgery to fix it. The TPLO surgery (Tibial Plateau Levelling Osteotomy) is very expensive and will cost £4,380. He is insured, but this leg is treated as a preexisting condition and is excluded from insurance. This surgery is the only solution to make him walk again and continue to be the best boy he is. He is my rock. I can't work due to my illness and disability and that's why I'm asking complete strangers for help. I'd do anything to save my best friend, my rock, my service dog.

Thank you, to each and everyone who can help us. Every little helps me get my baby boy fit again.