The moulds I use are from superstore and cost $2. They work ok, but you could use anything you have, or make your own.
Yield: 7 popsicles (around 2 cups of liquid)
4 organic lemons, juiced
zest of half a lemon
1/4 tsp liquid stevia (use up to 1/2 tsp if you like it really sweet--I like to maintain some tartness)
11/2 cup plus 2 tbsp coconut water
Mix all ingredients in a pour and pour into popsicle moulds. Freeze for at least 4 hours.