Duct rods:
This one is on a reel -
https://www.electrical-contractor.net/The_Store/KI/Images/rodder_1.jpg This one is in pieces -
http://www.cerro-ems.com/ems_files/drain_files/drain_images/2253TD-02At.jpg The reel could be used in your application (does it go 450'?)
The pieces are infinite (just get more) - limited only by your own strength and bends in run.
I have used both, each has it pro's and con's.
I have even used wooden rods that have wheels on them - they do help (manhole situations in a duct bank)
