I'm not an artist, but I do have the cover art for Cosmic Horror. Since CH won't be released commercially, you can use it on your products. It's such a cool drawing, it'll be a shame if it won't be used at all in a printed product. I can check if the artist (Melvin de Voor) will allow it. In addition, I have several sketches by Melvin intended for Cosmic Horror. I think he'll like his art's being used in printed product.
Let me know if you'd like that and I'll ask him.