Depending on the light fixlture, manufacturers offer additional rods for an upcharge, but typically they are the higher end fixture manufacturers.

If your electrical box is angle mounted in the ceiling, a chain is your only option

My concern is the way the downtrods will look, hung from a 14 foot ceiking.

Fine, use chains.

Show us the picture of the fixture and the space. If the ceiling is 14' then the chains or rods will only be 9ft or less..........correct?

How big is the fixture?

With a 14 ft. ceiling, the fixture is going to be mounted a bit higher in the room than if it was an 8ft ceiling.