This seems to be distantly related to the hering salad we have here, and that can be found in every supermarket. Only some ingredients are different:
Hering, but not salted, instead pickled (sour)
red beets
apple
onion
mayonaise
sour cream

and thats all. I always liked it - occassionally. And its really cheap, too.
And we don't use old cans to serve it in. :)