I know what the cost of having diabetes, I have it. I tried looking up some sites to see if I could help you but there are not very many.Can you get your insulin through insurance? Maybe you should ask your vet if he has samples he can give you. I know most vets have samples like your doctor does. That might help some.
Try the Humane Society first since they have knowledge of knowing where to go for help. Also look up the following. labrdorlifeline.org, and imum.org. maybe these will be of some help If you find that you want be able to keep up with the rising cost of medicine, please give your pet to the Humane Society for adoption. Your pet will be be getting his needed medicines. Good luck and God Bless You. Watch his eyes carefully for cataracts. It don't take long for them to develope in pets or humans.