Male me a emp slot jammer that works on all aristocrat slots and all australian slots -- 2

Hello i live in australia and own a few pubs that have slots in them with a bunch of friends . And they have asked me to get one made up that will work on all current slots and that is disguisable in a handheld walkman or radio or mp3 player for the demonstration id like it to be hidden if you can garentee me of this and that its garenteed to work and to arrive on time the please hmu