Window Problems

Ok, on my girlfriends driver side door, her window fell into the door, so i start investigating, the sashs' are still on the windown, but the plastic pieces that are on the regulator (i think its the regulators, the guides/tracks for the window) are broke on one side and missing on the other. Is there any way of replaceing these plastic pieces, if so, whats the proper term for them? and if not, will i have to replace the regulators?