It’s a .222 Numrich also has the rivits but I don’t know if it’s compatible with .222I believe that the 788 uses Remington 700 rivetted extractors. Someone will be able to confirm if this is correct.
You did not mention caliber.
Long out of production by Remington.
GunPartsCorp lists a reproduction extractor #8930D @ $23.76, repro rivet #85760E @ $5.79 for .308, etc. size.
The old rivet must be removed along with the remains of the extractor.
Installation requires a little anvil to support the rivet head while rivetting is done with a small hammer.
Ok thanks for the helpRivets for .222 are longer than those for the .308 size.
If it comes to it, rivets can be made.