If you need a new one, Hirts Gardens has them on sale right now. Not sure if it is because I am in Ohio, but I have found the shipping to be very reasonable.
https://hirts.com/vanilla-vine-orchi...f-vanilla-oil/
I would guess that this is cold damage. If you have any part of this vine that is solid and green (even with those black spots), and a few leaf nodes, cut the damaged part off (leave the part with black spots), treat the part with black spots with isopropyl alcohol, and let dry for a day or two. Then, dip the stem in rooting hormone pot in NZ sphagnum moss or sand, cover the entire thing with a clear plastic bag that has a few holes in it and keep warm (if your refrigerator is near a window, the top of the fridge is usually a good place. These often grow under trees for a while so they can take a little shade while they are young.
If you do not have rooting hormone, it is okay. The warmth is most important for getting a plant to take root.
Good luck!