My 13 yr old Scottish Terrier heavy eye discharge. Please help!

[GGGboxing]

Ok so Homer, my 13 yr old Scottish Terrier, started to have noisy breathing like he was stuffed up and crusty discharge on his nose and around one eye. We went to the vet, he said he believed it was related to a tooth abscess/infection. He wanted to do all sorts of tests and thereapies which would cost $1700! I’m financially strapped and was recently laid off and I’m currently looking for a new job. No way I could afford this. I explained this and the vet said the least expensive option would be an anti inflammatory and antibiotic. We did these and everything got better. Fast forward three months and the symptoms returned. I purchased more of the antibiotic online and started that and I’ve done the antibiotics for 5 days now. The noisy breathing is gone and the nose isn’t discharging anymore, however they eye discharge is extreme. 3 days ago I woke up and Homers entire left eye was invisible because so much discharge had come out and dried up and formed a grey looking eye patch sort of thing. I was horrified. I cleaned it with warm rag to get rid of it all but this discharge keeps happening to where I have to clean it off 3 times a day to avoid it completely covering his eye. From my research I’m thinking he may have an abscesses 4th molar. I haven’t taken the best care of his teeth which makes me feel terrible now. Is there anything more I can do at home with maybe different or stronger antibiotics? I’ve been using Clavamox. If it is indeed an abcessed 4th molar, it would have to be extracted at a cost of about $1000 or more which I don’t have. Homer is my best bud, and besides this issue, his health has been outstanding for a 13.5 year old dog. I don’t know what to do. Thanks for any suggestions or support