I've not seen one anywhere with the right threads.
Best I've found is either a blank or one with a smaller hole that could be bored out and threaded.
Steve Jordan on Youtube suggests using an exercise weight as a source for a blank.? I don't know whether that's a good idea or not.
You can also get taps of that size, but IIRC, Dennis said the spindle thread is a little off from 1-1/4x12 and it's best to cut it to fit.
chrisser