Where do I get allergy reducing eggs?

In Purina Pro Plan LiveClear Cat Allergen Reducing Cat Food there is a special type of egg where the chickens are raised with cats, causing the eggs have a protein that neutralizes the main protein in cat saliva that causes allergies in humans, but I don’t want to use the food, I JUST want the eggs, but I have no clue what to look up, or where to look. If you know please let me know. 🙏

-Reason why I don’t want the food: I wanted to get it for my cat due to my, my family, and a close friend’s allergies, but the vets suspect he is sensitive to chicken meat, as it is a common food sensitivity in cats and he has having belly issues; he could eat chicken eggs but chicken meat is not ideal, and the number one ingredient in that food is chicken meat.