I can recommend 3Dhubs.com. Seems like quite a few people around the world have 3D printers that are idle most of the time, and thus are happy to print orders for others . If you have the drawing and upload it, chances are someone nearby can print it fairly cheaply. I have printed a bunch of STAX jacks, speaker waveguides, etc, this way.
For STAX jacks, I found the below specification of dimensions from a previous KG post, and made the CAD file using tinkerCAD, which is a free online tool. It can't do complicated stuff, but for a cylinder with holes in, it works well enough...
STAX jack
Imagine the socket as a 6 pin with the 6th pin missing, but at position 0,0 (x,y)
The rest of the pins are at
0,.2175
-.2175,0
+.2175,0
-.1087,-.1883
+.1087,-.1883