Here is that one I have hopefully pic loads up. I have asked several people on this one and the majority say to weld up where it was ground and leave the bolt in place as it is quite unique. Do a search on anvil repair Gunther method, that's loaded with advice.
Pretty sure that is a Hay Budden. It looks like it broke right at the seam. Later Buddens were made with two pieces like that and forge welded together. The earlier Buddens had a tool steel top plate. This design is better that is a nice anvil, pass it on to your Grand kids and tell them to do...