There aren't any "Bearing Buddies" on a TM. At least not any I'm aware of. The greasing system goes right in the end of the axle and has a dust cap with a rubber center cap over it. You pull out the rubber part and pump grease into the fitting (zerk) in the end of the axle. I just pull the wheels and grease the bearings by hand - I think its more reliable and less chance of grease ending up on the brake shoes.
Usually the grease zerk is made of a softer metal than the axle, so you can buy another zerk at Schuck's (or Auto Zone or whatever auto store you have close by) and install it. I would take the old one to compare because there are quite a few choices.