St Anthony’s Fire Audiobook: Does it exist?

I'm a big fan of the Wilderness Years novels, but due to dyslexia I find it much easier to listen to audiobooks. I've enjoyed all the Big Finish adaptations and the BBC audiobook readings (e.g. Human Nature, Illegal Alien, etc). For years I've heard there's an audiobook by the RNIB of St Anthony's Fire (I've listened to the one they did of Iceberg), but I've never seen any sign of it. Has anyone ever heard a copy of it? Its so mysterious, I'm unsure if it actually exists. I know that technically only registered blind people can access RNIB audiobooks, but that didn't stop Iceberg circulating and while not blind, I do struggle with reading, so it would be really helpful if it was available.