Cheytac Bottom metal options

[E4aker]

Im considering building a 375 cheytac. Im trying to figure out what bottom metal options their are. I have found the metal from Baer, but saw wondering if their was others. Im thinking about using a mcmillan stock and stiller action. I found this picture of a build using a whidden composite stock and an unknown bottom metal. This is about what im looking for. Thanks