You have several options. If you can find a larger fiber or wooden pole, you can use that as a new support for your pothos. Because the roots of the plant likely fill the current rootball, you'll probably have to place the new stake to one side of the new, larger pot. You may need to train (tie) some of the longer vines to the new post to get them started. If the plant is not too firmly entangled with or rooted into the existing pole, you may be able to detach the plant and remove the pole. Otherwise, simply leave it in place as a secondary support.
You're other main option is to take cuttings from this plant and start a new one.