I haven't used this enough to evaluate it but it's another one to consider. It's an Alps Conquest folding pole. They sell per each, not as a pair. It folds to 15" and extends to about 5'.
1 review I read complained because the lock lever allowed it to come apart in mud. I guess he never heard of tightening the lock nut on the lever.
Edited to add: never mind. I just found out that they've been discontinued.