I don't support breeders. I'm in animal rescue and can't justify supporting the breeding of animals who have millions of their species homeless already.
If allergies are an issue, volunteer at a local shelter and get involved in cat fostering. That will let you know how your body will adjust to a particular cat without making a commitment you cannot uphold.
There are no truly hypoallergenic cats. Pet allergies depend on your immune system, your exposure (sometimes more pet exposure is better), your air quality, the pet's food, the pet's health, the pet's grooming, and more. If you decide to foster or do a trial, get an air purifier and vacuum daily with a hepa filter vacuum. Feed high quality food and have another family member brush the cat regularly.