Help us safe Mr Loaf's eye!!!

Hi, my name is Igor, and my wife and I are helping stray cats. We have an old guy in one of our colonies who got sick. We managed to trap him with our hands yesterday once we saw the condition of his eye. We found a foster who we already paid $150 in advance. Now, we need help gathering funds and scheduling an appointment through the rescue with the Eye Guys doctors. So far, we are waiting for some rescue to help us with the discount; otherwise, we won't be able to help him. He is around 15 years old, a very nice cat. Nobody ever managed to neuter and vaccinate him, which is very sad. Now, since he is old, we don't even know if it's safe to have this surgery, but we need to talk with the vet. Anything will help; please share! ‍⬛❤️