Well,,mines a Model 335,,but the link looks about the same.
Heres a few pics.
The end of the 'pin' is full round, not half round.



It does look like an assembly of the flat lin k,,two cone shaped pieces and the pin itself.
The pin in mine is slightly 'off', being outboard a bit farther on one side than the other. I suspect it's just a force fit (hammer) and that keeps all the pieces in place. The geometry of the cone shapes and the forces pushing inward keeps the assembly together during use.
Try knocking it apart and replacing the pin with a new one.. Otherwise file off the end and drill it out for a new pin as suggested. A press fit, soft solder or even loctite shold be sufficient to hold the assembly together for whats expected of it.