88 stratos dt150 cant find grease fitting for steering

[blugunnman]

i have a 88 stratos 18 ft with a dt150 when i steer to the right it is great nice and smooth, but to the left its a different story, sometimes it takes to hands to turn, at higher speeds that is, there is 2 piston like things on steering where it connects to motor on one of the pistons the grease fitting is shot cannot find one like it checked marine stores and car hardware stores do you have any ideas, could really use your help..