Boyce, linking this post with the one about rising anxiety levels, I would suggest to that you do get a sleeper, it may be well worth it to you, and have your meals, or most of them, served in your room. You will still want to walk around and explore the train while it has stopped at longer stations.
Walking through coaches and sleepers is pretty easy, there is always somethng to hold onto...that is not quite so true in lounge cars and dining cars.
I do not use a cane, but am subject to a certain kind of dizziness problem myself (had it for about three years) and that is my advice. Of course you may be so adapted to your cane that my advice may be overly-cautious.
