please help me save sisqo

3 weeks ago my boy sisqo had ran away from a house that i moved into.he was gone for 3 weeks till he returned two days ago with a bad wound and infection.he somehow got his leg caught in his collar,so his collar was embedded into his leg.he went through all that pain to finds his way back to me.i reached out for help but was turned away from vets. till today when waikato spca had offered to pay for a consultation for him.which I am very grateful for.I have just received word that sisqo need a operaton and his leg to be amputated.they will not do it unless payment made first.waikato spca have been supportive.A note about myself,i have been a worker since 16 and few years ago had a injury which has affected my financial situation but as sisqo is my family,i couldnt let him go as iv had him for 7years.so now im am for the first time reaching out for help.please help my boy.sisqo is also held at carevet chartwell hamilton,for those who donate and would like to know how he is getting on.thank you