do NOT substitute for the sugar!
you have to be careful when pickling stuff - using artificial stuff can have a serious effect:
"Some sugar substitutes are not approved to use in canning because they are not stable once heated. Those would be NutraSweet, Equal, and Saccharine. Also Truvia, a by product of Stevia is not shelf save either. "
and
"Sweetened pickles and relishes using sugar substitutes such as Stevia and Splenda will work but may add a mushy texture and have a strange aftertaste. You can use honey for your pickling but use 3/4 cup of honey for every cup of sugar. For sweet pickles use a dark honey rather than light. "
http://www.sbcanning.com/2011/08/sug...-approved.html
me, i'd just work them into my diet: 1 cup of pickled beets, sliced, is 106cal according to fitday. i love pickled beets but 1c is probably way more than i'd want to eat at a sitting.