Single-start 2mm lead openbuilds lead screw blocks?

Openbuilds has 4-start (8mm lead) and 2-start (4mm lead) but not single-start (2mm lead) trapezoidal screw nut blocks. I’ve found and but neither is solid. I tried cutting a tap from a piece of single-start lead screw, but it deformed the edges of the threads enough that there’s still a little play when I run it through a delrin test block. Not as much play as the normal brass nuts, but I can still feel it.

I found which might work better than my hand-made taps, but does anyone have a source of solid 2mm lead screw blocks, to openbuilds specs so I can get out of this particular rabbit hole?