The Leki which francois mentions (link above) comes with a camera mounting screw (image from link):
You'll want to put a ballhead on it. In my very limited experience with a similar pole, a ballhead + QR plate made the stick much less useful for walking (but turned it into a functioning monopod). There is also the consideration of carrying your camera on the stick/pod (depends on camera, distance, terrain, shooting style, etc.).
The NeoTec monopod (also mentioned and linked above) is more battering ram than walking stick. It's heavy, very solidly built, and has a grip that is oversized for my hands (small man's, large woman's). I think of it as a great "city-pod". You carry it -- you don't walk with it, much less trek. It is highly recommended as a monopod (
B&H reviews).
I just recently looked into a number of combination walking sticks/monopods (all under 150 USD). Nothing (in that price range) met both functions well, in my opinion and the opinions of the many reviews I read. Understandably, it depends on what your needs and intended uses are.