A submersible well pump assembly has a motor that rotates a drive shaft within the pump. The pump has a number of pump stages, each stage having a diffuser and an impeller. A bushing is fixed for non-rotation within the diffuser. A thrust runner sleeve mounted to the drive shaft has an outer diameter surface in sliding rotating engagement with an inner diameter surface of the bushing. At least one seal ring is mounted to the sleeve in sealing engagement with the drive shaft to block the entry of well fluid particulates between the sleeve and the drive shaft.