Maybe you could find a totaled Runner (Tacoma too, perhaps?), pull that plug and snip off enough wiring to have a 'pigtail'. Then carefully snip yours out and solder-in the pigtail - with the battery disconnected. I wigged out my 3rd gen briefly when soldering the ABS wire that broke with the battery still connected.
You also may be able to identify the pin inside the plug, then buy a replacement pin (probably a pack of them) and the tool(s) to push out the old pin and crimp on a new one. More research there, but certainly less than $400.
Best wishes!