Ah.
Well, I have a Sachs IGH, probably an S7, that I will have to make a shifting rod and the bit that goes on the end to push the rod in when the cable is pulled. That part's probably easy; the hard part is making the shifter itself so it correctly shifts to each gear position; will require experimentation.
I don't expect I'll get that done soon, but when I do I'll make a thread for it, so maybe it would help you fix yours then, as a spare for whatever you replace it with right now.
If you take pics of what's left of the bits on your shifter rod / cable attachment / etc, I might be able to suggest something you could build a new one with, if you're up for that.
FWIW, I believe from what I've been reading on various sites, that as long as it is from the same hub series, so same number of gears, you should be able to use the shifter rod and end piece from any other SRAM hub, and probably from any Sachs hub of the older version of the same series/number of gears. So if you find anyone selling one of those hubs, complete (even if the hub itself is broken in some way), you could try it on yours.