Original wood taps are pretty hard to get. For some reason, everyone saved the dies, (rectangular blocks of wood with a cutter and sometimes handles on the sides).
but the taps are much harder to get.
They made modern ones and they are pretty cheap. Woodcraft Supply and Rockler and all the regular dealers carry them. About $30 I think. I bought a 3/4" set (yard sale 5 bux for me)
This is the size of broom handles and probably the size of this clamp.
The tap works really good and effortless. But the die is very persnickety.
The stock has to be ---very perfect-- wood stock, the cutter razor sharp and set just so, and you have to slather everything in oil to the point of slop city, gushing.
If a guy wanted/needed to make dozens of them, all these things can be taken care of.
Just to make one though, its kind of a pain. At least in my experience.
yours Scott