Hello,
Welcome to ehealthforum and thanks for writing
Vaginal repair surgery is used for strengthening the muscles and ligaments of the uterus and genitls which drop down due to pregnancy,chuld birth or menopause.At such a young age it is not recommended and if any it has to be ruled out first whether you require it or not.
Regarding the cost it depends on the type of surgery,stay in the hospital and location where you are staying.It can vary in every other place.
I would advise you to get a complete examination done as what is the cause,if you require it or not and recommended treatment.Sometimes slight dislocation can be corrected by means of exericse.
Kindly visit a Gynaecologist for careful evaluation.
Take care!