1985 Case 450c final went, do I need pinion?

Lost final drive on one side on case 450c dozer, ordered final with pinion from a equipment place in texas, they only sent the final, no pinion, the pinion on the machine is not missing any teeth, just shows slight wear maybe a little of the hard facing wore off, how can I tell if it will hold up? We put on the final it works fine just wodering if I should find a new pinion and put it in as well, which is a way bigger job, but want the fix to last?



thanks for the advice