Injector Overhaul: Repair or Replace?

Please help. I already wrote something before. No response.

I wanted to replace my injectors. Even though it's a BMW, they are Bosch injectors.
New costs: €320 per piece.

Someone told me that it's possible to replace parts on the older models. Apparently, there's a repair kit available. Does anyone know more about this? Which Bosch service centers can do this?

What are the costs involved?

It would be a good idea to call Bosch.
Why are you even creating a second thread for this?