sit ... a stool is the way to go, and you can still strap your bass and kind of sit on the edge of a tall stool with your right leg up on the rung (if your right handed) and left on the floor .. looks more like you are leaning if you are concerned about the looks of it, otherwise sit and enjoy your time playing ... I also use 4" Italia straps with suede inner thast keep the bass in place and slides less on the shoulder which helps ...
BTW, I hope your pacemaker keeps winning for many, many years to come
