It may not be as rootbound as you think. Take it out of the pot and clean off all the dead roots and any medium. You might also have two keikis. Once you have it down to live root only get a pot that the roots just fit into. If there are some long strands, cut them so they don't wind around the bottom of the pot.

An extra pair of hands will be helpful at this point. Get a bamboo stake and put it all the way to the bottom, then position the plant so the canes are in the center and in its final position. The other hands can add bark and work it down around the roots. Once the bark is firm enough to pick up the pot without coming loose, then you are done and tie one of the canes to the stake.

If you have two keikis and decide to separate it into two plants, do exactly the same twice. You may find that you need a very small pot. If it is tippy, set the plastic pot inside a larger clay pot for stability.

Your plant is a warm growing type of Dendrobium that likes temps in the 60 to 90F range with moderate humidity so you have to think about where you are going to house it.

Mine are in glasshouses because they die outside due to unsuitable temps and sometimes low humidity.

Perhaps Zone 9B might be OK??? or perhaps you will have bring the plant inside during winter?

In any case find some complete culture notes for Phal type Dens via google to add to your info.

thank you both.
I assume I should wait until it finishes flowering before I attempt to re pot it.

If you are enjoying the flowers, wait. But it could be repotted now, and if the misalignment bothers you, do it.

This type of dendrobium likes to be rootbound, so it is not stressed too much. The roots hanging over the edge look like now is the time to repot. Soak well in lukewarm water and ease out of the pot. Richard told you the rest. If you give this a fair chance it will reward you.
Ann

Thanks Ann, I did the deed. What little media was in the pot was completely broken down,and I soaked it and eventually managed to get the roots untangled. Once I got it upright and presented it to my wife, she looked slightly upset and said she liked it better the other way!
I'm giving it a little sugar mixed into it's rainwater, I've read somewhere it helps keep the plant from shocking after transplants, and is safer on a stressed plant than fertilizer.
Thanks again, everyone, for your input.

If you're going to give it sugar, give it molasses, which contains sulpher and ingredients that aid rooting.

Tell your wife to wait a couple of months and it will be right back to the way it was.