They possibly used a 30-06 action and opened it up to suit the slightly bigger case diameter of the 9.3x64 and altered the follower to suit, although you may be able to use a follower from an 8x68S model as the shoulder position is similar. If done correctly and everything works as it should and providing the cases don't rattle in the magazine, then it would be a good purchase IMO.

Waidmannsheil.