Use the following support document to determine the charger required for your specific model / year of MacBook Pro.
click here ➜ Identify your Mac power adapter - Apple Support
The A1398 model number you provided corresponds to a number of different Macs from 2009 all the way to 2015, but based on the CPU and speed, you probably have a mid 2014 or mid 2015 model, so the 85 Watt Magsafe 2 charger is what you are looking for:
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85W MagSafe Power Adapter with MagSafe 2 style connector
- 15-inch MacBook Pro models introduced in 2012 through 2015