Where Can I Buy Kitten Milk Replacer?

I have a 7 week old kitten that has been diagnosed with a type of inflammatory bowel disease. Can I give him something to help? I was hoping it would be the milk replacer as well as the probiotics, as he seems to be lactose intolerant and his symptoms are very similar to those seen in Crohn’s Disease. He appears healthy otherwise and is not thin or underweight for his age.

What can you do if your cat vomits due to illness?