Here is the quote for the new injectors under part number 4326784. At the moment Cummins only shows 4 of these available.
Eventually it appears the original number 4954374 will transition into 4326784.
It would be at least six weeks leadtime for these new ones. It could be more as they are not really fully active yet.
Just an aside, there have been reports about the Chinese Cummins partner selling outside of China. They are not supposed to do this according to Cummins and Cummins says that many of the parts are "inferior". I think Cummins is in a bad situation as they made partnership deal with the Chinese and now it appears that they are competing
against Cummins worldwide. I haven't seen any of these parts, but I have heard some horror stories.