Stack Social has a Call of duty Bundle:
https://stacksocial.com/sales/the-call-of-duty-bundle
For $39.99 you get:
Call of Duty 2
Call of Duty 4: Modern Warfare
Call of Duty: Black Ops
Call of Duty: Black Ops - Annihilation & Escalation Content Pack
Call of Duty: Black Ops - Rezurrection Content Pack
6 Days left