Careful with that CB antenna, 5/8 wave ones have matching transformers in the base which restrict the frequency range. If you go that route a fiberglass 1/2 wave dipole type (two sections, no radials) or 1/4 wave ground plane would be your best bet. Just cut the top section down to 53" and they'll resonate just fine, don't forget to put a plastic boot on the fiberglass one to waterproof it.
As for a discone, one must have a vertical top section and a few of the "radials" must have loading coils both for VHF Lo Band operation. Ignore published frequency ranges, they're purely advertising BS lies and deception. Check the photos before you buy, you should easily see what I'm talking about.