This is a remix of Xoan's thing #85809 which is itself a remix of Josef Prusa's original Y motor mount for the Prusa i3 (with 8mm threaded rods). It provides three attachment points to the NEMA 17 stepper vs. only two in the original Prusa i3 part.
It is compatible with any Prusa i3 using 8mm threaded rods (for example, Twelvepro's improved Prusa i3).
I have smoothed out and reinforced Xoan's part (eliminating what I thought could be potential stress points) and cleaned up the source code a little.
The OpenSCAD source file is included with proper attribution to Josef Prusa and Xoan.
I printed this part in PLA with 35% infill and 0.6mm wall thickness, and it seems to be extremely strong. Very easy to print as there are no bridges.