How large is the root system of a cedar bush 2.25m high and wide?

Not too large to be transplanted, if you are good at doing that and are very strong, but you will need to take a larger ball, wider and deeper, than most will be able to do. The problem is not the 6-7' high, the problem is the major width. There are machines that do this, but probably not worth the cost and maybe not able to get to the bush. Cedar is a common name, and we do not know the actual plant identity from it, which can matter. If the concern is excavating near it, the edge of the foliage is the usual guide to what it could survive.