yea like already said as long as the axle is good, and the surfaces of the axle housing where the bearing sit are good, id say you would be alright.
i would put a zerk fitting in there. i have one and the bearings were in there 5 years before i got the quad, and i have had it five years on top of that and they have not ever given me any problems
all i do with my is pump grease into it until some comes out of the end of the axle housing (which is usually on the sprocket side). it doesnt hurt the bearing at all, but it could push the seal out but i have never had a problem at all. sometimes after i ride in deep water and the put grease in, it will push water out then grease will come after all the water is out. hope this helps