Tent poles work well. Good size, stiffness and disassemble-abilily. I no longer run a second rig at fests, but a few times I made up a quick clamp-rig from a Windtech clamp, a discarded three section shock-corded tent pole, a spare pair of mics and recorder - pulled from a discarded tent and random stuff I had on hand back at camp.
I'd not worry about the internal cable routing unless/until you decide you want to run whatever setup you settle upon regularly. If you do, I'd use tech-flex or some other cable sheath to protect the cable at the bends, maybe in a double layer.
Running cables along the outside of sectional (non-telescopic) poles I found it easiest to first attach the mics to each end, then hold the pole up in the air horizontally from its center, letting the cables dangle freely with its connector end(s) held together, then rotate the pole around its own axis (twist it) to spiral the cable around it. The cable should spiral nicely and evenly inward from the mics in towards the center from each side. Do the opposite to disassemble the mics from the pole.
^Nice. Good flushness with minimal gap and just the grid extending.