If you have any kind of hobby shop in your area they should have the clips.
One of my friends came up with A really cool set up. He has balsa blocks glued to each side of the fuse and has his RX leads glued to those facing up, he just plugs into them so he doesn't have to fumble around everytime with the leads. I know this isn't any locking system but it does make it an easy in and out thing.
So far I have never had one of my aileron leads vibrate apart and I don't use anything to lock them together. I know, it only takes once.