Choose depending on your location:
https://highscoresave.com/preorder-darksoft-namco-system-2/?number=DSNAMCO2
https://www.saveyourgames.it/en/prodotto/preorder-mid-september-darksoft-multi-namco-system-2/
http://www.candycabclub.com/product/system2
I'm not an expert on Konami, but although the motherboard is the same as the one in Taito X2, the PCB will not boot with TX2 bios as it has a bootlock chip.
Account lock was finishing tomorrow but I just removed it. He should be able to check them now and answer if he wants but since the beginning of the year, his activity was less and more drama.