From their announcement:
A couple of months ago I posted that the Reaver would be available soon, then it did not happen for very understandable and unavoidable reasons – like the Armorcast production facility being under water!
After several weeks of backbreaking labour and much treading of water, Armorcast is more or less dry and casting again. So the Reaver is now available and up in the store. Go on over and buy a bunch! They are happiest when a pack of them are pulling down one or more PCs.