Wiring combo outlet & switch but box w/ 3 wires
Since you broke the tab, you have (electrically) two separate devices, so you will need one extra wire instead of two. But no big deal.
You will need one extra piece of black wire and one extra piece of white wire, and two wire nuts to replace the existing wire nuts.
Screw colors are based on the picture &amp; instructions from the linked switch. Others may vary somewhat.

Existing black switch hot wire (the one that is combined with two others) goes to black screw on switch (top right if switch on top)
New black wire connected to the other three black wires in a wire nut and to the black screw on receptacle (lower right)
Existing black switched hot wire (the one that is by itself) goes to brass screw on switch (top left)
New white wire connected to all the other white wires in a wire nut and to the silver screw on receptacle (lower left)