Drilax 1 3/4 inch Diamond Brick Concrete Block Masonry Hole Saw Heavy Duty Wet Dry Use 1-3/4 inch 1.75 inch Single Pack: Amazon.com: Industrial & Scientific
6 in. x 8 in. x 16 in. Red Face Concrete Block-66408 - The Home Depot
Amazon.com: Acacia Grove Mini Cinder Blocks, 12 Pack, 1/12 Scale: Toys & Games