If like me, you lose and then buy some of the tiny detent balls for dustcovers on Uberti 73s.   Here's a cheap replacement. #2 steel shot from a waterfowl shotshell. One shell replaces about 150 detent balls, which are about 0.150" diameter. The Fed shell I cut open even has copper plated shot. Just don't use a #2 lead as it's going to wear quickly.   Beg or steal one from your duck hunting buddy or your own hunting rounds.   Good luck, GJ