. although the second link is in German , but no doubt a fellow german in the forum could translate if needed
There is not much info in this link. It mainly states that the motor is 100 steps per rev.
30 Ohm per coil
7,5 V / 0,25 A
Dimensions 42 * 42 * 32 mm
Shaft dia 5mm * 10/28 mm
This looks like one of those tiny steppers recovered from 5 1/4" disk drives
Oh and by the way. German Websites have .de (Deutchland) in their adress.
This was Dutch.
EJK