Far too much effort, there's a much simpler trick.

I have a somewhat larger lathe with metric leadscrew, but that's just the "inverse" of your issue with the same solution.

The problem is, that a 127-tooth gear wheel won't fit on the end of the spindle (or on the banjo), it's simply too large.

The solution is to use a 66/52 transposer pair, which will fit.

That gives a ratio of 1.2692, which is close enough to 1.27 for all uses I've ever had.

Now, whether Prazi offers those, I don't know, but 33/52, 66/26 or 33/26 transposing will work the same.

EDIT: OK, it seems Prazi don't.

Apparently you have a complete set, which is 30, 35, 40, 45 .50, 55, 60, 65, 75.

The missing 52- and 66-tooth gear wheels shouldn't be too hard to find.

The specs for the SD300 are pretty standard:

Material: Nylon/Delrin, most probably reinforced.

Module: 1

Width: 8 mm

Width at hub: 10 mm

Pressure angle: 20 degrees.

No idea about hole size, but that should be really simple to measure on your machine.

Cheers.