You need the Old Style Extractor,,the short one with the separate flat spring attached. It comes as one complete part,,spring attached.
Hard to find these days. Wisner's makes a fine repro of these.
They also make a repro of the early New Style extractor for the 39 (Machined).
But the Old Style is Out of Stock.
You might Email them and see when they might have a batch back on the shelf.
Marlin Lever-Action Rimfire | Wisner's Inc
They have a few of the commonly needed MArlin 39 parts for rebuilds.
Numrich is another possible source, Prices can be out of sight on some things when compared to Wisners.
Numrichs doesn't have the Old Style Extractors in stock either. They may just get them from Wisners and resell them anyway
Numrichs NewStyle extractor is a Stamped Steel version, not the Machined out one.
The CArtridge Guide Spring and Screw are a common part no matter if from a 39A, a Mountie, or any of the Special Commemorative editions, etc.
Jack First Gun Parts has lots of MArlin 39 parts,,but I don't see any Old Style (flat spring) extractors pictured.
They do show quite a few different available rear sight options at the end of the Model 39 parts pages.
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