Years ago, at a prayer breakfast, I received communion with others at our table, the bread and wine (juice, of course) from handmade trays. These were "smaller than a breadbox". The individual cups rested in dimples in the base. A handle ran lengthwise, padded feet under the base and a groove through the base allowed them to stack, like these seen at a church supply house. (So much for illusions of a quaint English workshop.) At the breakfast, a small oblong plate covered the groove and made the apparatus self-contained. The "breakfast model" was smaller -- 8 or 10 served, I think -- so perhaps more modular for small congregations.
I would love to see plans and a buying list for these, either vintage or new.