A retinal fold is different from a geographical fold. If it is a retinal fold, then you should complete the RD/OSD test. If the bitch comes back clear, send a request to CERF...they'll give you a breeders option.
If it is a geographical fold CERF will fail the bitch. Dr. Lionel F. Rubin has done extensive research in regards to retinal and geographical folds. I spoke with him personally in regards to geographical folds. He feels that a unilateral geographical fold in the Labrador Retriever is not a problem and he would clear a bitch for breeding. Bi-laterally he would not approve. He says he doesn't see a big problem with geographical folds within the Labrador Retriever breed.
I would contact him before making any decisions. Good luck!
Dr. Lionel F. Rubin
1116 St. Andrews Rd.
Bryn Mawr, PA 19010
610-520-9430