Some countries have different rules about the "operator area" than others. Of course, Amada sends machines all over the world. Machines that come into the U.S. have the wires there for the start button, but no start button installed because of the OSHA definition of the "operator area".
The long and short of it is, look through the Granger catalog and find a momentary contact button that looks pretty. Cut a hole where u want the button. Pull out the electrical schematic and find the appropriate wire numbers. Open up the little cover plate where all those other buttons are already and look for the wire numbers you found in the schematic. They should be labeled and just crimped or taped off.
I suppose if you need help finding the wire numbers make another post and I will try to find them for you.