This is what it looks like. I looked on molex but can remember the other company that sells various connectors.

 

Anderson??

 

Morning
It is a propriety connector not going to find a direct replacement I think as it was not a main stream design.

IBA store leadership bought out the Widder inventory when they when widder went out of business.
https://ibaestore.com/index.php

They may have what you want...
After that, Id look at converting all to a standard SAE plug

 

I actually have a couple left over but instead of converting to SAE, I went to 2.1 mm coaxial connectors as used on most heated gear for at least a decade. Easier to connect even in the dark and more efficient (less resistance)...

 

Thats a good choice for sure..I was thinking on road repairs I guess when I mentioned SAE.... you can get an SAE cable at any truck stop, electronics place or auto store to scavenge the end and some wire to make a repair.
But not everyone needs that advantage, and so 2.1 mm coaxial connectors is a outstanding suggestion