The Ring Doorbell Transformer (UK)

I was just wondering why the genuine hardwire transformer is constantly out of stock on both the Ring (UK) and Amazon (UK) website. Ring tell you of the dire consequences of using a non Ring DIN transformer for a mains wired Ring Doorbell in their literature but then make it impossible to purchase a genuine Ring DIN transformer. I want to purchase one for better or worse so can someone from Ring please tell me how I can purchase one. THANK YOU.