There will probably be several options for an electrical source to serve a new outlet. For instance, it is likely there are several suitable wall receptacles in any given room to extend the circuit to another room or another floor of the house.
Hold the outlet box against the ceiling about midway between the joists and trace the outline with a pencil. Cut a channel from one joist to the other, the same width as the outlet box. Use a drywall saw to cut gypsum board and a reciprocating saw to cut wood lath plaster.
After the installation is complete, cover the notch with a metal shield, available in the electrical section of home stores. Repair the wall over the shield and the hole in the ceiling to finish.
Split the sheathing on the cable leaving about 1/4in still covering the wires. Cut the sheathing to remove it and strip off about 3/4 inch of the plastic insulation from the end of each wire. Avoid nicking or scratching the copper wire while removing the insulation.