I have hunted for such a monopod, but never found one. I've been walking with a cane for 25 years now, and hoped I could find one that would allow me to leave my cane in the car. I did buy a cheap one at a local Sportsman's Warehouse, but like any such combined function device, it wasn't the monopod I needed (not tall enough or strong enough), and not the cane I need (inadequate handle).
When I get into "wilderness" terrain, I carry two cameras - one with a long lens for wildlife and the other with a kit lens for landscape. (I usually also have a backpack on my back.) The long lens camera is mounted on a monopod and carried over my left shoulder, and the landscape camera hangs on a Cotton Carrier holster on my belt on my left side. My cane is in my right hand.
I find it easy to quickly hang my cane over my left arm to shoot with the monopod+long lens camera. Switching to the landscape camera takes some seconds longer to be ready to shoot, but I can usually keep up with the landscape pretty easily - it moves slower than I do.
I've grown to really dislike hanging a camera on my neck, which made to belt holster very attractive, and it has worked very well.
Full disclosure: I'm 77 with an artificial left hip, artificial right knee, and no feeling on the bottom of my right foot. Hiking is nothing like it used to be decades ago, but my adaptation has worked, even though I can't do long distances any more.