You want motors with around 0.44Nm of torque (4.2kg.cm, 62oz.in), and a voltage rating of 1-3 volts so the chopper driver has plenty of overhead. You can use motors with less torque for the axes, but the extruder really likes a very strong motor.
From the motors on that page, I think the last one (ST4209L1704) is the best match, and ST4209S1404 should work for the axes if you don't mind getting different types of motor in one order, and don't mind having to use a particular one in your extruder, and don't mind not being able to get really high speeds. Remember if you're making a prusa that you need two steppers for Z
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Wooden Mendel
Teacup Firmware