The plants available have leaves a little over an inch long. This plant is seed grown. The first photo is one of my stock plants and the last one is the size plant available.
There is also a larger size available here: https://www.nsetropicals.com/product/anthurium-carlablackiae-3-leaf/
These plants are about a year younger than the larger 3″ size listed. They are still juvenile, and are just barely starting to show veining