There was a fella' on here awhile back that was customizing a 1/2 ton van. He was using every nook and cranny in the van, had some excellent storage ideas. I can't remember the name of the thread but he also has a blog about the conversion.
One thing he did was to use the doors as part of the storage solutions. The back doors will hold a lot if properly outfitted.
I can relate to bin issues. I have about a dozen in a storage shed, one I dedicate to parts and tools. I'm always shifting them around to find something. If you need a shallow cabinet under the window, I'd suggest to DIY it.
An alternative might be to buy wire drawer units, cut them down, and attach together. I have one with mesh drawers and the drawers don't slide very easily. A bungee or single stay would keep them in place.