They've been out of the labs for a while. CATL has been producing sodium ion batteries for a few years already. They are used in some of the cheaper cars there. But nice to see more companies getting sodium ion to production.
But if that's what you are after, get yourself a nice second hand Nissan Leaf or similar. With the older ones, you might have to replace the battery. But that's not the end of the world in terms of cost. Some of the older ones are selling well below 10K$. A battery replacement would set you back 3-5K$. But it would also increase the resell value of the vehicle. And with a good battery, these things can last a long time.