when i built a trolley, i had the outlet at the bottom and just connected the pole hole. Usually just buy a longer length of hose to fit inside the pole so you dont have to move it about much. I dont know of anywhere that do small reels suitable, but have seen one on a omnipole trolley.
see
ht tp://www.omnipole.com/125%20trolley%20300dpi.jpg
Or you can wrap it around the top, but its usually a pain. I would just put a longer pole hose on, about 20ft after fully extended.