I would give the folks at Winnebago a call--there's a good chance they can get you what you need:
Service Administration
(800)-537-1885
For inquiries related to your current vehicle, service, or dealer inquires, please have the following information ready when making your call:
• Complete 12 digit serial number
• Date of purchase
• Selling dealers name
Note: If you own one of our motor homes and have a question about it, we encourage you to contact us by phone. We find phone communication allows us to more quickly resolve your issue.