Pelican has some delrin shift coupler bushings. I have used the old black ones before and they are slightly sloppy. The delrins look like a nice alternative, but I can't find any legacy info on them. And, they are 4x the price so I would like some kind of endorsement before I commit.
http://www.pelicanparts.com/cgi-bin/smart/...20%281973-76%29