Hi @OASimen,
The button we use has a 5A current rating, but it doesn’t contain a fuse.
I expect it will be quite difficult to find a button that meets that specification, but if it’s helpful the button in the switch is the 30-3UL (as specified in the Switch - Contents) 
If you’re unable to find a direct button alternative, you might want to look into using the Switch between a power pin of the Raspberry Pi (or Pixhawk) and the input to a logic-level MOSFET with a suitable power rating for your application. That kind of setup is discussed a bit here, although that’s in the context of using the Pixhawk to digitally control a switch, whereas with the mechanical switch you may be able to use one of the 5V pins of the RPi, which should be easier to find suitable MOSFETs for.