The 8, 10 and 12 are single 3 ohm (really work out to close to a 4 ohm load) and the 13 is a dual 1.5.
To the OP the difference between 700 and 1200 is not going to be very much on that sub because of power compression.
Play music, not sine waves. Keep the gain set low. Keep the volume down. The amp you're talking about won't make that kind of power into the load that sub will present it with anyway.