Haha-it is for a fellow gun nerd for me, although I must admit-I know absolutely NOTHING about all the variations of Mausers. I have one, a cheap looking Soviet-Capture K98 I use in my Soviet Partisan impression.
Nice catch on the DP, I am saving up to buy one. Also saving up for a PPS-43, as I already have a PPSh-41. Does the DP have interchangeable barrels? I really hope so, I wanted to blank adapt on for use.