If you are considering a change of suspension components I think you would be better off going to a KW Coilover Kit V3
https://www.kwsuspensions.com/products.html or a coilover made by Bilstein
https://www.bilstein.com/us/en/.
Coilovers will give you the ability to adjust height and firmness with a spring/shock combo engineered to work together. The cost of these after market parts will also probably be much more favorable than trying to buy the corresponding BMW parts seeking to do an OEM 704 conversion.
If your car is really new like say a 20 or 21 then you may need to wait for after market parts to be developed. I think the newest KW parts for a G30 are for a 2019, but maybe it's just their configurator is not updated.