Solved! While it is definitely no standardized plug, my solution is that I found a cheap LED extension cord on ebay, gonna hack a few of those apart.

I bought a few of these LED stripes when on sale and want to run them from a common 12V DC source which means I need to replace the wall warts. I don’t want to hack off the plug from the stripe if possible, so if possible, I’d like to build a distribution box that offers the same socket as the wall wart does. Any hint would be appreciated.