So all I need is some of these + the pins + a crimp tool (why is it so expensive?)
You don't need a high dollar AMP crimping tool.
Many auto parts stores have inexpensive crimp kits for the tool, and might even have terminals that will work.
Your parts lookup skills are commendable.
I don't know if it is in your comfort zone but you could open the PSU and solder in a jumper.
Cleanest look obtainable.
YMMV
I don't want to mess up the warranty, so that's why I want to just attach a connector.
Also I think I can attach the terminal to the cable with just some basic pliers and, no special crimp tools is required, but nevertheless it is a good tool to have.
Do you know if any of these is for terminals: http://dx.com/s/crimp+tool