How about this ? Approximately 37 euros => 41$
https://www.instant-gaming.com/en/1437-buy-key-steam-civilization-vi/
At the bottom of the page it gave the required system specs! Hmm:
Minimum Requirements
OS: Win 7 64
CPU: Core 2 Duo E8500 3.16GHz / Phenom II X3 710
RAM: 4 GB
GPU: GeForce 8800 GT / Radeon R7 240 v2 1GB
HDD: 15 GB