I would concur with most of the advice above.
However, the skill level of your chosen gunsmith is equally important to the method used.
I have repaired exactly the break you have with laser welding and it is still working fine but I approached it with my brain turned on, chose my filler metal carefully and hardened and tempered to achieve toughness not wear resistance. I made sure all filing was carefully radiused and polished.
If you let someone do it who doesn't understand the requirements, it could fail very quickly.
If you go for the gold standard option and have the whole leg remade, the straightness and filing/machining the flat of the split stem is critical or you may have all sort of other issues.
Frankly, if the gun was mine and I didn't have access to a first class gunsmith, I would go for laser welding the original two parts (probably using stainless filler rod as we have discovered it mops up a lot of the carbon, reducing the chance of cracking) and then temper to a fairly soft state to give you toughness. It will wear but if you keep it clean it will probably see you out.
