If you want, you could always try to open the Saturn motor up and see if you can fix something. I did this with a dead dreamcast motor. One of the brushes in the motor got bent backwards somehow, I was able to 'carefully' open the motor and bend the one brush back to where it should be. It runs now, but I keep it as a spare.
I'm not too familirae with the inside of a Saturn, but if you can get to where you can read some numbers off the motor you could try to Google the part number to see the specs and find a suitable replacement.
Unfortunately, there could be reasons other than the motor being blown that the motor isn't spinning. First thing to do would be to hook that motor up to a suitable power source to see if it spins at all. If it does, your problems are probably elsewhere, and you should keep an eye out for another saturn. Worst to worst, the saturn you have now probably has some good parts in it. If you can't get it working, at least you have a parts machine.