Getting lifter bushings installed is anywhere from $500-$700 depending on the shop. Yes, it is extremely expensive. But my understanding is they have to have jigs for a small block mopar in order to do it. And I wouldn't let them do it unless they have done a small block mopar before. Its not the same as a small block chevy.
You can have the bushings drilled for oiling prior to being installed for hydraulic cams or if you want the lifter to have pressurized oil for push rod oiling.