As of this writing, there is for The Mark by Edyth Bulbring. I have conducted extensive searches on major audiobook platforms, including Audible, Google Play, Apple Books, Audiobooks.com, and Everand (formerly Scribd), and have not found a listing for an audio version. The searches returned results for other books with similar titles or for the ebook version of The Mark only, with no audiobook format indicated.
Look into South African audiobook platforms (such as LAPA Publishers or local streaming services), as the book is highly celebrated and widely distributed in its home country. Conclusion
If you need a direct link to the Audible page or help finding it on a specific platform, let me know.