The trick here is to find a tray insert that will meet your wants and needs. It likely will not be one offered for CRVs. More along the lines of going to a shop that specializes in a wide range of plastic storage containers or compartments, with measurements of your arm rest cubby in hand, and pick out what makes sense for you. And probably some thin foam sheeting that you can cut into shapes needed to properly fix everything in place without any rattling around due to vehicle in motion.
Honestly, if it was me, I would design the perfect little storage tray for my needs, and then go get some PVC plastic sheetpanels and custom cut and then glue and foam pad the exterior for a custom tray and just pop it right in. The nice thing being, this does not take highly developed crafting skills, and can be changed or replaced over time by simply making a new one when new needs arise.