Petcircle has a sale on for these that only just started. Cheapest I can find at this point anywhere.
The chart is in the middle of the product webpage. You can safely chop these capsules in half for a downsize.
Eg., A single medium (green) can be two doses for a small (yellow) dog.
Curious… Do you have a source for that claim? Manufacturers advise against splitting tablets as "the mixture may not be homogeneous". Not that I buy that explanation but I'd like to be on the safe side.