Walt raises some good concerns. I personnaly have never seen or known anyone to load such light bullets in the carbine. My Hodgdon #26 Manual lists more options in the pistol section than the rifle section. It lists bullets as light as 77grs in both sections. In addition to Walt's comment, you also could have a very unstable bullet in flight. It may give very poor accuracy, plus if your using it for pest control, it may not do the job. Also, consider your own point, a pistol bullet at rifle velocities.
Yes, Speer still makes the Plinker. It is a 100gr half jacket bullet. It is constructed so that none of the exposed lead contacts the barrel. I have used these bullets on gophers and they work wonderful. They also function the action of my Inland carbine as if I were shooting 110gr ball.
Hope this helps. If you have any more questions, please post or email. :-)