1970s 2 Liter Coke bottle value?

I found two coke bottles that say 2 liter size and are both in pretty good shape. one has the cap on it still but is empty and the other does not have the cap. Ive dont minor research and found out they were made around the 70s. The coke logos on them only say Coke with Trade-mark (R) written under it, no classic or nuthing... I was wondering about how much they would be worth? Plz help in ANY way! Thanks!