I know what he is making but a Plastic front sight ( Innova ) on the " Bay " made £30 at the weekend !
This would requiring boring & threading with a steel insert of 1/2 Thread suitable for a silencer ! Like these ! The steel threaded insert would sit on the barrel ( 9mm ) a perfect fit to ensure alignment , IE No clipping .
I originally made these using the Plastic front sight & They were OK, But not what was required & The front sights are now rare.
Ged.