This is a good example of the loco tender 6 wheel power plant for your tired loco. It may be best for you to enquire what savings may be possible.
HORNBY R832 PRINCESS or R066 DUCHESS OF SUTHERLAND TENDER POWER UNIT VGC
HORNBY R066 DUCHESS OF SUTHERLAND or R832 PRINCESS CORONATION FRONT BOGIE GC
HORNBY R066 DUCHESS OF SUTHERLAND OR R832 PRINCESS & CORONATION R834 REAR BOGIE
OO Gauge Tri-ang_Hornby BR Princess Loco Tender Top_Spares or Repair_Code 3_vgc