Can anyone help please?

You could try looking on your search engine for caravan scrap yards/ breakers yards or salvage. When we had a total loss the insurers had it collected by a salvage yard so they could use some of the parts. 

Not sure where you are situated but I found 3 within an hour from here in North Wales.

I will ask a Moderator to move your post from Stories, where few people will seat, to the section on the forum for either "Caravans" or "Parts and Accessories" so you may want to check there for more replies.

Mods - Could you move post to the appropriate section please.

I am not sure if its the same with caravans but motorhome habitation doors are often made by a third party supplier. This company suppliers replacement doors so it might be worth a try Habitation Doors

David

These people may be able to help…….https://caravanpanels.com/collections/bailey-caravan-parts?sort_by=best-selling&filter.p.product_type=Locker+Lid&filter.v.price.gte=&filter.v.price.lte=

caravanpanels.com       If the above does not work