I don't really know what needs the Rockies have to make guesses here. Cargo is an untouchable. He's unquestionably their best player and a league mvp level player who's only 27. Also if he begins any kind of decline his contract is going to becom an albatross around his team's neck. Here's his remaining figures and it's a backloaded contract
YR Age Salary
2013 (27) $7,500,000
2014 (28) $10,500,000
2015 (29) $16,000,000
2016 (30) $17,000,000
2017 (31) $20,000,000