I have a pocket organizer by SPEC-OPS, seems to be the exact thing as the diplomat minus the hook and loop field on the front above the mesh pocket. Great piece of kit IMO, I keep a couple of space pens, burt's bees lip balm in the elastic sleeves (need to add a mechanical pencil though) along with 2 3x5 rite-in-the-rain tablets. Has room for a bunch more, like I said great piece of kit.
As far as the p-38 vs the p-51....ive had both. Never had a problem with my 38, but the 51 opened all the time. Took a couple of good scratches and one good chunk outta me before I took it off and threw it in the trash. I'll stick with the p-38 thank you very much.