According to our [[Topic:DualShock 3|guides]], the DualShock 3 controller uses 7.2mm Phillips #00 screws to secure the rear cover to the controller. Looks like you can get them [https://www.amazon.co.uk/Controller-Playstation-Controllers-DualShock-Gratify/dp/B01MQ5HSDR/ref=sr_1_1?s=videogames&ie=UTF8&qid=1500410003&sr=1-1&keywords=7.2MM+Long+Philips+%2300|here]. Good luck!