Huh, occording to
wikipedia, this off label use of regular birth control pills is approved by the FDA. So it's off label, but it's more than just understood by doctors to be OK, it's actually gov't approved.
"The combined or Yuzpe regimen uses large doses of both estrogen and progestin, taken as two doses at a 12-hour interval. This method is now believed to be less effective and less well-tolerated than the progestin-only method.[4]
It is possible to obtain the same dosage of hormones, and therefore the same effect, by taking several regular combined oral contraceptive pills. For example, 4 Ovral pills are the same as 4 Preven pills.[5][6] The United States Food and Drug Administration (FDA) approved this off-label use of certain brands of regular combined oral contraceptive pills in 1997.[2][5][7]"
If I recall correctly, any birth control pills will work, you just have to know which pills of the month to take, so you get the ones with the proper hormone levels.