Severe arthritis in itself is not a reason to end a dog's life because there are many different types of pain relief (my b*tch is on Tramadol for degenerative joint disease - arthritis - and is still an active part of the household and enjoys life) and acupuncture and magnetic collar have been known to help some dogs improve mobility and minimize discomfort/mobility problems. Ten is not a reason to end a dog's life if its discomfort can be managed with veterinary medication and complementary medicine. Arthritis aside, if the heart, lungs, kidneys and live were all functioning normally I would opt for removal of the eye and the tumor could be excised in the same operation if there was one - bear in mind that not all tumors are malignant and removing the eye could be curative if benign.
The dog may lose its eye sight, but then again may not and I have owned a dog with acute hearing and excellent sense of smell that adjusted easily to his deteriorating eyesight over the years - not possible to save it in his case. You could upgrade your pet insurance policy but I would be surprised in the provider would pay out to the new level of maximum benefit for the treatment required now. Typically it would be limited to the current level of cover.
With pain management for the arthritis, I would opt for surgery and enjoy what time I had with the dog while I had it.
I'm so sorry for your dog. It is such a hard thing to know what to do. We had to put down our 9 1/2 year old Newfoundland 2 yrs ago because he couldn't move his back legs.
His spine was messed up(there is some long vet term). All I can say is that the only person that really knows what the right thing to do is you & your family. You will know in your heart the best thing for him.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.