Here we go guys.
Files for the Stella Tips so you can modify, machine or 3D print your own :)
The inside thread is 7/8-20 UNEF-2B, MINOR DIA: 0.8250-0.8280
If anyone is great at modelling threads (I've never bothered) we could model the 3D threads, and then print the parts and they should just screw on... I'll host the files for that also. :)