They come from your regular host supplier. They’re typically 1 1/8" diameter (at least that’s the size made by the Cav— company that supplies hosts to many parishes in the US). There’s nothing special about them. Many parishes use them on a regular basis. Only people who happen to be used to the larger ones might notice the difference.
They’re actually considered “standard” size, and the others are considered larger size. Take a look at the description of a ciborium in any religious goods catalog or internet site. If they say “100 host capacity” there’s usually a note explaining that 100 refers to 1 1/8 hosts.
