https://www.etrailer.com/RV-and-Camp...ophy/AS25.html
These Brophy ones appeal to me. They have a bracket that fixes in a very narrow profile to the side of the truck, and the stairs compact down to a very small package I could store in one of my basement boxes when not in use. They seem to just drop into the bracket easily for use.... They would not require a lot of work to install, or use, nor take up floor space, or force me to revise the current box structure.
The only downside would be some ability to access the side boxes, but its relatively unimportant. I could station them to block only one set of boxes. The same website has an affordable railing as well for about $87 the folds up and is easily removable.
Alex.