No, they will break. The only way to pick up spawners with a silk pic is with a plugin. MV does not have that plugin currently.
The plugin is called silkspawners, maybe you should suggest it. It would also be helpful on skyblock. EDIT: I am suggesting this.
I think it's been purposely left out so people can't move spawners. I think it's fair enough considering that it is factions, not OP Factions(OPFactions has this). You can buy certain spawners in the shop though, I believe you cannot buy hostile mobs though. It has been suggested before that hostile mob spawners(such as Zombie, Skeleton, Creeper) be added to the shop at a high price before, but nothing was made of it.