Repairs to a garden wall

Job Desciption

The brick wall of our front garden is damaged in several places. The wall is around 30 years old and the mortar isn’t great. The left-hand side of the wall is cracked, presumably either by the trees/shrubs behind it, or possibly by collision with a vehicle (please see attached photos).  The brick caps at the top of both pillars have broken off, so we would like these replaced with white pier caps (pyramidal) if possible. The brick caps on most of the columns in our estate are damaged in a similar way (or have been repaired).