Hi
Bass Pro shops offers the cordura covered rod tubes that have carrying straps/handles for reasonable prices...about mid $20's. I believe they would be lighter than PVC tubes. Some are available to leave reel attached with a little room for a small fly box. Cabelas also offers the cordura tubes but I believe they cost more than BPS.
You might find an eagle claw rod or another brand of about 6 or 7 ft at walmart. I realize you want to avoid more gear purchases but you may encounter unrepairable damages to your good gear and if that matters, check out some cheap but useable gear at Walmart.
I think at one time Daiwa offered a very compact 7 piece spinning rod and reel combo. My boys each took one to prep school with them.