There are also some imported copies of the old military HS-16 up
for auction from time to time.

...... Some 1/4 in plugs are designed to clamp the old pin connectors
under screw heads.
Jeep and the Group...
The HS-16s work fine with the S38 and are usually pretty cheap. I bought
several from Electronic Dimensions for $5ea. The 1/4" plugs used with
tip pins are considerably larger than regular jacks. If you run across
one of the large jacks unscrew the backshell and the tipjacks might be
inside. Crimp pins from Canon MS series connectors work great on tinsel
wire and the relay jacks on back Johnson gear too.

EdZ