Help for Little Onyx

I'm Terry Corson. I have been Onyx caretaker for 2 1/2 years.  Two weeks ago she came for breakfast with a broken front right leg. I have been trying to find her help. People I have spoken to want me to put her down. I'm not putting down a perfectly healthy kitty. 
I'm on the minimum amount disability so I can't afford the Vet bill and I need help. Since she's gone so long with the break her leg needs to be amputated. Please help Onyx get relief from the pain she has been in.
From what I can see since she doesn't let me get close to her anymore she got it caught in some kind of trap.