They are rare and ultra expensive when they do come up. if you have a can sr or Jr you can make a lead up with either a ji772 or a tesla plug to use a 110v outlet, other wise I think you will be in for a long wait or an expensive purchase.
I had to do this the day I brought 637 home... it worked fine charging at the dealership, then wouldn't charge at home. The GFI end had went bad some how! Very glad it was a $15 fix and not something more substantial!