Hi Scoop! I buy directly from Visbiome. This is the exact product I purchase: https://www.visbiome.com/collections/all/products/visbiome-capsules-2-pack?variant=25325572681
Another probiotic recommended by UCLA is a less potent, less expensive option: Culturelle: https://culturelle.com/.
I opt for Visbiome due to having lost my colon back in 2000 and keeping my GI flora in check is of the ultimate importance. Visbiome is expensive but worth it for me. It has been tremendously helpful.

An interesting note: According to Chinese medicine, the lungs are the sister organ to the colon. That being said, in my opinion, GI health is especially important for those of us with lung issues.