Filler is a great option for the lips. I like Juvederm, as it is very soft and yields a great looking and natural result. Cost can vary depending on the physician and your location. I would recommend seeking the advice of a board certified dermatologist, plastic surgeon, or facial plastic surgeon. They are all great choices, and will be able to advise you after examining you in person. I hope this helps, and I wish you the best of luck.
Dear Qwerty13 Thank you for your question! Lip injection with fillers is an art!! You have a thinner upper lip and to get the desired shape - it may take a few injections of HA to achieve. With Warm Regards Trevor M Born MD