Help Benney live

This is Benney my soon to be four year old Australian Shepherd. I got him for my 15th birthday and he has been the love of my life ever since. I have never had any medical problems with him and he has always been my happy healthy boy. About a month ago I noticed he started having pain in his right eye. I took him in right away and the vet misdiagnosed it as just an ulcer that should heal up with some ointment. Flash forward about a week with no improvement and him being in extreme pain. Not trusting my vet I took him to a specialist who then diagnosed him with glaucoma, which as strange since he was so young and healthy, but I didn't question it. Since he became completely blind within the week of treating him for an "ulcer" I made the decision to have his eye removed. After his surgery, he seemed back in good spirits. He was eating and playing with his beloved ball like nothing ever happened. Into the second week of recovery, I noticed that he was having trouble breathing so as soon as the pet hospital opened I brought him in to see what was wrong.  They took a chest X-ray where they discovered that he has blastomycosis which is a fungal infection that doesn't show any signs of affecting the dog until it is advanced.  All the other vets I took him to didn't even know to test him for it since it is uncommon around here.  I had them start treating him right away. The first two days were very hard on him and he had to be hooked up to an IV and have an oxygen tube attached to him since he can't breathe on his own right now. It's been four days and the vet has even tried using a double dosage to encourage a reaction, but so far it is not working. I only have two more options when it comes to what else I can do for him. Either try another medicine at a different vet who has it, or euthanize him.  I visit him every day and see all the life shining in his eye. He is fighting so hard and no matter how much is struggling he wags his tail and tries to play with his ball as soon as he sees me walk in. He's not ready to give up yet so neither am I. The medical bills are adding up and I can't keep on affording his treatments much longer. I have put all my savings into trying and save him. He has so much more life to live and isn't ready to give up yet. Please help me get Benney the funding he needs in order to keep him alive. He is such a great dog and has not lived his full life that he deserves to live. At this point, every little bit helps so thank you so much for reading my his and helping in any way you can.