The notion of an unsalted pickle is oxymoronic. The very essence of the word itself is salt--from the Dutch word 'pekel' which means brine.
There have been a number of manufacturers of salt-free pickles but their products were discontinued for lack of demand. There are some decent salt-free recipes online; most are essentially processes using vinegar as a preservative.
You can call 'em pickles, but the'll never taste the same as 'kosher' dills.

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