There is no need to pay a lot of money for fancy sitz bath salts. These products mostly have the same ingredients (they're mostly just salt) but may also have unnecessary ingredients. It's cheaper and more effective to prepare sitz bath salts at home. That's what I do.
All it takes is combining salts (Epsom or sea salt) with dry herbs (or fresh if you want) and natural oils. My favorite sitz bath salt is sea salt with dry chamomile and sweet almond oil. Sometimes I also make it with dry lavender or lavender oil. Both are very soothing, relaxing and promote healing. New mothers must try a homemade sitz bath!