yeah you can buy a slider from a headshop that prob would be best and since it is plastic i would take a nail and get it hot and let it melt through the plastic big enough for a metal pen in it then put some rubber cement or jb weld or somethign that will keep it from leaking and keep the pen in there and then get a slider fro ma headshop and sick it in the pen you gonna make sure the pen is big enough so the slider will go in and come out easy