hello !
thank you to all of you for the good job. The 1x1 round brick seems to have another
alternate item number for the metallic silver color. I have found it on the replacmeent
parts shop of the lego shop : looking after the ecto-one ref 21108 on the parts
shop
https://www.lego.com/fr-fr/service/replacementparts/sale/choose-brick
i have found the 18860 reference.
Have a good day an keep on the good job !
Thank you !
stephannie