I am currently producing the sector map that I will be using for Into the Breach. Had finished the preparations, looked at the blank slate and thought "Might as well save a blank copy". Fast forward to a wee bit later where I decided "Screw it. Let's let everyone have it." As far as I know there is a better/real one out there, but this was good enough for me. It's not quite as long as the regular map, but its all good.
All I did was use MS Paint to edit the Calixis Sector map, copy blank stretches of stars, copy the world types and then set it all to a blank map.
To use it, just find some extra backgrounds on google of space themes and crop them to add a touch of color, then just copy and paste the planet types on the key (on the right) and then type in their names. I used "Georgia" font, size 12, bolded for the text.
In the bottom left corner is the green dotted circle in case you want to have several planets in one system.
Feel free to ask questions. Otherwise, enjoy!