I've measured the TF of 500ft of RG58C/U cable to see if the loss is about the same calculated by that piece of software i've found.
I've measured 33.4dB attenuation for the LCOM cable, the calculated value is 32.1dB for some unknown RG58C/U cable.
So i think we should go ahead and calculate the required length and try it.

This is a picture of the 500ft spool we have. As you can see there is only about 1.5inch on that spool, the rest is empty. Height is a few inches.
So regarding the size we can easily have several 100m of cable in a small package