Hi Davy,
You're right of course about duff tubes. Monitor came in with the tube ends burned off due to plastic and corrosion - seem to go together with a bit of heat, so borrowed some from a screen smash on an old 4:3 which were just a bit short, not having a 16:9 24" smashed screen about at the time.
With the LED Sammy, you're getting a bit technical - Don't mind the bleed through as only happens with a dark screen, so not a bother.
Called on a mend recently where chap had a console 'wind up and scratch' with a folded horn - Sound quality was amazing, but guess records only lasted a couple of playings with a half pound tone arm and steel needles.
Seem to recall that in a 40's 'Wireless World' or Maybe 'Camm's Comic' someone suggested using a thorn from a rose bush - Quieter but less destructive, if could get it to fit the holder - Chris.