Yes, Winniebago parts seem a bit expensive ... but I consider the convenience of getting an exact replacement part whenever needed as well worth the extra $$.
For instance, I recently wanted to add an additional lock to an overhead cabinet door to help prevent it fron opening when traveling offroad. I checked at a couple of local hardware stores to get what I thought was a "standard" latch (from probably Ch**na) to add to the one already on the cabinet door. The local stores had kindof the same latch alright ... thinking their's was exact I bought it and upon getting home ... found it to be slightly smaller than the Winnie originals, so it would not fit right nor be as strong. I picked up the phone and ordered the latch from a Winnie parts supplier by giving them only the VIN of my Class C motorhome. The exact latch type and size - even in the original hard to find bronze color - arrived shortly. IMHO, this kind of ability to keep one's (8 years old in my case) rig in original configuration - is a fantastic Winnie service.
