While this may not help in the short term, If you look on the Walmart website and can find the bike you are looking for you can request an email alert for when the bike is back in stock and order it then for delivery to your home. I just did this a few weeks ago and within a week the bike was available.
They are fairly easy to assemble especially a single speed cruiser.
While I hate to reward scalpers CL and FB marketplace can be good resources for used bikes.