Well, I managed to remove the broken crank and replace it with an old Sugino Mighty Comp I have (vintage 1973).

I went looking for a replacement Campagnolo crank. They are out there, at least they are on ebay. The thing is, I don't have (and don't want) an ebay account.

I'm looking for some sort of online/retail seller who takes credit cards.

Later today, I will post some images of the two halves of the broken interface.

Right now, I'm going for a ride. It's 70 degrees, sunny and a cool breeze is blowing in off the ocean. Yeah, I am outta here, dudes!