I bet some will have never heard of these. I didn't until last night. You dry stack them then fill the cores. For those who have heard of them, where do I find them? There is a few manufacturers I found but no distributor info. In Australia they are sold under the versaloc brand name, not to be mistaken for versa-lok retaining walls. EZ-bloc is one I found and then there was another that had a minimum 15k block order. Any suggestions?