Cracked lintel

[Haz]

Hello

i am planning to get solid wall insulation done but the surveyor pointed out that my cracked lintel needs to be repaired first. would you know roughly how much this costs to be fixed and do I need to ask for a certain type of builder to help fix this? Photos attached.

Thanks

 

[Haz]

Also to note, this is above the main entrance door. Thank you