It looks like it’s a common rail inj pump..
The timing is set at the factory with different keys in the drive shaft of the pump..
U r gonna need a puller to pop the gear off tho..
The reason those pumps fail is: bad supply pumps..& dirty filters..& running the tank to empty..to where it sucks up the crud at the bottom of the tank..
MOST manufacturers will NOT warranty a pump without purchasing a new supply pump also..
Good luck