Scott,
I first noticed my upper rudder hinge get a little loose in the first two hundred hours.  I have found loose rudder hinges on other planes as well.  On mine, I pressed in a new bronze bushing.  For some reason it was a bit tighter than the original when new.  Once pressed in, the 1/4 dowel on the rudder would no longer just slide in. This turned out to be a good thing.   By swinging the rudder while working it down, I got the rudder back on even though I had a slight interference fit in that upper bushing.  Just as with the larger hinge pins, by removing the ability of the 1/4 inch to get hammered back and forth against the bushing, wear has been eliminated.  The replacement now has around 800 hours on it.    As part of my preflight routine I grab the top of the rudder and shake it side to side to make sure the bearing hasn't developed any play.
Longer bushings are a good idea if they fit well.  Another option is to machine some from stock and ream them undersize since the bolt/dowels are under 0.25" as well.  I haven't had the need to go to that extreme though.
Chris Zavatson
N91CZ
360 std.