I checked "the list" of handguns we are allowed to buy from someone who is out of State.
I found only the CZ P-01 and the CZ SP-01. Check for yourself, please, as I may have made a mistake.
"Handguns Certified for Sale"If your EXACT pistol is not on "the list", you cannot sell it into California. A P-01 is not a P-02, no matter how nearly identical they are.
The magazines may not be sold here, either. It is not clear to me that an FFL is authorized to receive high caps, even with the intention of reducing their capacity before delivery to the customer.
There might be some wiggle room here. Perhaps you can disassemble them before shipment to the FFL and they are just "parts". He could do his mods before assembling them into ten rounders.
There is always the possibility there is an exemption for your potential buyer, too. Are they LEO or a movie-making company or ... I remember reading of several exemptions from what applies to we civilians.
Look at all that complexity.
I used to be more up-to-speed on these things but, as I never needed to apply the info, I am only working from old recollections.
I hope this helps in some way, even if it is just to ask the right questions.