My sprinkler system is pretty old and has worked great for over 20 years. I believe I need to replace the diaphragm in 2 of my control valves. I believe the valves are Rain Bird EV 100. Can anyone help me locate these parts? I did find a website that shows the Irritrol HR-1 diaphragm which looks like the diaphragm in my EV 100. Does anyone know if the Irritrol HR-1 will fit the Rain Bird EV 100?