If your motor still turns you might only need a new top -part # 6SCM1T which is in stock now.
see below

Motor # 6SC M1
Motor # 6SC M1
Item# 6SCM1
$4.25
Availability: Usually ships the next business day

Product Description

Motor # 6SC M1
If your M1 motor still turns you might only need a new top -part # 6SCM1T

Accessories

Replacement motor TOP ONLY # 6SC M1T
Fits on Snap Circuits, Snap Kits and Snaptricity motors.

Can be pushed on gently and get your motor working properly again.
$0.25
Availability: Usually ships the next business day
6SCM1T