Replant or remove a mature tree that has been leaning and growing at a sharp angle for years...
Answer
Oh my goodness. It's too bad that the tree wasn't straightened earlier; my thought is that the tree is too mature and too "tall" at this point to be able to use a stake to straighten it, which is the method used for a young tree. However, you say that the trunk is straight and branches are even. The fact that it is surrounded by Belgian block and concrete also complicates matters since the roots have probably grown horizontally as well as down. Yes, an arborist would be able to determine whether the tree can be dug up and replanted. It might mean root pruning to get the tree out, and a good arborist could advise you as to whether this would be successful with this particular tree. Be sure you choose a registered and certified arborist. Good luck!