A little better description of the issue might help. You can buy a new plug with pigtail (wires already on it) then solder the new connector to the old wires, with heatshrink tubing over the solder joints to weatherproof them.
If there's enough wire left on the old connector, just solder it back together and heatshrink it. If there is not enough slack to do this, insert a new piece of wire between the two, but since you should only need an extra inch of slack if that, you might be able to trace along the wire and find an area to pull a little bit of slack free on it.