Since you do not give me the model of the Class C Winnebago you have, the only thing I can tell you is that it was probably an Onan Generator. I cannot tell you what model Onan it was.
Your best bet is to contact the manufacturer of your RV Winnebago Industries. You can call them at (641) 585-3535 and they should be able to tell you the model generator that was originally installed on your motorhome.
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