The keys to my outside compartments on my 1996 Chev. chassis, Regency style, Barth had worn out. From information on this Forum, I found that the keys and locks had been made by Southco of Philadelphia and Concordville, PA. See http://www.southco.com
Upon an email request, they sent me two free replacement keys! These are the aluminum keys with broad handle, and tubular key barrel. Inside the barrel, the number 715 could be seen. The replacement part is E3-26-715-19.
If you need replacement keys, try emailing Southco. The email address was on their website as info@southco.com It was very nice of them to replace my keys with no charge, not even for shipping.
Allan of Solvang

or you can buy them at any Winnebago parts counter.