I play senior hockey (Over 60) in two leagues with over a hundred guys in each league. Probably 1/3 of them have have knee replacements and some have had BOTH done. Yes, they went through a Sports Medicine specialist doctor and they were in good shape (strong leg muscles, not over weight, good cardiac health). They usually get it done at the end of the season (mid April) and are back skating at start of next season (mid-September). Lots of walking excercise after surgury (some are out on the stree 2 days later). League won't allow you on the ice until you get 90 degree joint rotation, so the pressure is on to get back in shape, asap.
What some have told me is that dealing with a bum knee caused major problems (as in need for replacement) with the opposite side hip. So, at your age and probably good health, "get the knee done". Shots only helped them with pain, not the deterioration and THAT lead to other issues.
My problem is that some of these guys with TWO new knees are still faster than me with OEM knees...