There is a very popular prayer book available called the Pieta Prayer Book. It typically has either a blue or orange cover and the image of Michaelangelo's Pieta on the front. The book is full of wonderful prayers and is very affordable. We sold several hundred when we first opened our store.
Unfortunately, we found that the prayer book also contains private revelations from people who haven't even been recognized as Venerable by the Church and there is no indication that these revelations have been in any way approved by the Church.
Since we first opened our policy has always been “Good Faith. Guaranteed.” which means that we don't carry many popular books including the Pieta Prayer Book because of the private, unapproved revelations they contain.