Box saloon throttle linkage help

[Ivor Hawkins]

After way too many years off the road I’m about ready to fire up the old box saloon, but I’ve mislaid the little male end of the ball joint that bolts to the carb (zenith 26va) throttle linkage.
I’ve machined one up so I can get the car running, but it’s not ideal, does anyone know where I can buy one? I’ve searched all the usual places but no luck...