In large pot, combine 2 quarts water and lemon juice. Peel, core and halve pears, adding them to water lemon juice mixture to prevent browning. Meanwhile, in another large pot over high heat, bring vinegar, remaining 1 cup water, sugar, Sweet ‘N Low, pickling spice, and 3 cinnamon sticks to a boil; boil 10 minutes. Drain pears. Reduce heat to medium low; add pears, and simmer 5 minutes. With slotted spoon, remove pears to hot sterilized jars, allowing 1/2-inch headspace (or follow jar manufacturer’s instructions if different.) Remove pickling spice from syrup and discard. Place 1 cinnamon stick in each jar. Pour syrup over pears. Wipe rims with clean cloth dipped in hot water. Close according to jar manufacturer’s instructions and process in boiling water bath 15 minutes.