its bricks that are hard to findHah,you must live in an upmarket area? heck I could walk a few hundred yards and find some scrap metal to practice with ie Washing machine,Microwave,cooker skins and then there's the skips to rummage in ie steel shelving stands or post ect,ect.
Its there if yer take a car cruise around.
And what about computer cases?
its bricks that are hard to find there propping everyones cars up