All of the products below are available at most drug stores, without prescription (they're just sterile eye solutions, no "active ingredients", so they are appropriate to use every day if needed).
Expect to pay around $9 per box. But each box has at least 30 single-use containers, so it will last a while. Both of these products are "heavier" than regular "get-the-red-out" drops, so they are better at moisturizing. Also, because they come in single-use containers, rather than a bottle, they don't have any preservatives in them, so they're appropriate to use as frequently as needed.
See Allergan's website for more info.
Expect to pay around $10 each for nighttime gels. Used every night, one tube should last 7-14 days, depending on adult- or child-size portions.
These products also do not contain any preservatives or any other ingredients that would make them inappropriate to use every day.
Moisture Eyes PM, first repackaged as Advanced Eye Relief™ Night Time Lubricant Eye Ointment, now marketed as Soothe Night Time Lubricant Eye Ointment. See Bausch's website for more info and images of the new packaging.