ADK,
If you want to go "on the cheap", just get a sheet of skate board tape or some of that adhesive back stuff that they put on the bottom of tubs and showers to provide a non slip surface. They make the same stuff for concrete steps to provide a non slip surface in winter weather. Just trace a piece the size of your butt plate and stick it on. You can always replace it if it gets damaged. I've found it in Home Deopot
I've done that to several of my own rifles for the same reason.
SM