I have never had any dealings with them. But I think they may have been the company. That bought all the old stock when Cummins bought Onan. Onan at one time had a parts reserve center. Where all the old Onan parts were sent. If the factory didn't have the part. We called the center.
If that is true they should have a large supply of Onan parts. The best way is to call them and talk to them. They could be an honest company looking for customers.