If your customer is willing to pay for a more permanent repair, here is my recommendation; Based upon the Steinway verdigris saga and the understanding at this point in time we have not established a permanent fix without replacement, I take the second most viable route that appears to be next to permanent. If we assume the verdigris begins to show its ugly head about 30 to 40 years (correct me if I'm wrong) with exposure to the impregnated wax solution, we could reasonably assume replacing the pin would restart the 30 – 40 year clock, but we're faced with the current binding effects of the verdigris on the new pin. About 5 years ago I repined a Steinway verdigris action by cleaning the bushing with carbon tetrachloride, aka brake cleaner that can be obtained at auto supply stores. The pressurized can with a spray tube is perfect for squirting directly onto the bushing. Adequate ventilation required. About 3 cans will serve all the busing in an action. I experimented with this procedure about 5 years ago with no call backs yet. Maybe they will remain friction free for another 30 – 40 years.