If you're that desperate for something to extend the run between the brick and the laptop, just cut the cord in two, add the wire (remembering it may need be 3 or more conductors if it has an ID pin as some OEMs (like Dell) do,) solder it up and remember to put the heatshrink tubing on loose before soldering.
This takes about 10 minutes to do, less if you've done similar previously. If the power jack is not OEM proprietary and in the rare case that the power brick is screwed together rather than plastic welded, you can replace the entire run of wire and put a new plug on it.
Then again, if the plug is standard instead of OEM proprietary, you can just hunt down the mating socket and another plug at an electronics supplier like Digikey and make your own extension cable that plugs into it.