I am guessing very late 1960s or early 1970s, of course still a 'GM Mark of Excellence' product with the "exclusive five year warranty from Frigidaire and General Motors". It's an Imperial DW-IMN model. And it's only $30... though the seller says that water lines need to be checked for a blockage.
I am not able to grab this now... maybe in a different time as they say! But I was posting because it seemed such an interesting (and cheap) dishwasher that I thought that someone might be interested!