Oh no ! I've searched for a portable version of 7zip and found this one : https://portableapps.com/apps/utilities/7-zip_portable
I've never downloaded from this website before but it is linked from the official 7zip site so I'd deem it trustworthy, not sure how to help otherwise as even if I upload on another file hosting service it'll have to be some archive format since the game has multiple files/folders.
Hope this does it for you!