Major knee problem

I tore my right inside meniscus years ago and had several cortisone shots and finally operated on. 3 months later the same Doctor operated on it again. I finally went to another Doctor and with a fresh MRI he told me the first Doctor really BUTCHERED my knee and had to operate again. He said by then arthritis was going to be a BIG issues from the operations. In 2015 I was walking 4 miles a day 5-6 times a week. 2017 now retired my left knee started acting up. I'm getting by but with both knees now being affected mt co pays are to high to have a knee replacement. I'm almost 63 now but will probably have to put it off until 65 when I get Medicare. I looked into Stem Cell treatments but it was about 7500.00 per knee. Now kicking around trying some of those cremes made from Marijuana.