Rubber stamps, cut out of slices from an old eraser which I sacrificed to the project. The handles are formed out of a molding paste which mainly consists of paper clay.
After drying, the rubber letters will certainly have to be fixed to the handles with glue. I used a fine cutter and tools for woodcut or linoleum cut.
PS. Decided to replace the molded handles by cardboard, because the drying process will drive me nuts, I need it quick.