I hadn't realized that Wow had gone out of business. I wonder if it's because there are getting to be so many different makes, models, and sizes of mid and longarms that it's not really profitable anymore.
I have a Wow machine, a Singer 201 that was stretched to 18".
Since the machines aren't specialized, I think that any reputable repair technician would be able to maintain and repair your machine. I take mine to a repair tech here in town, he works on all types of machines.