Bushings can be "trapped" with some center punch marks around the circumference of the bushing. You just want to disrupt the metal that surrounds the bushing a bit. Kind of like a round peg in a now square hole sot of thing. Been done for ever on the thrust washers used in old motorcycle crank shafts. Even in the shop manual for my Harley. Where to get them? Try these folks.
http://www.dormanproducts.com/p-66649-14055.aspxYou might need to give them the size inside and out side to get what you want.
