Yes, you can buy it. It is also cheap but it's quite difficult to get the exact result from them. I also had the food intolerance and allergy problem and I eliminated it from https://www.intolerancelab.co.uk/allergy-2/. The expert member of this laboratory helped me a lot to get my life free from pain and disease.
According to me, you should also have to visit any intolerance lab and check it properly to get the better life & its better as compare to home test.