Cool idea fatdog, I'll have to keep that one in the back of my head for the future
I had just finished gluing the new bulb into place after drilling out some of the frame to accommodate it, when I noticed the deck kept auto-stopping. Uh oh. There's a white wheel right next to the flywheel whose shaft has cracked off just below the metal plate it sticks through. There's a nearby notch that appears to have been linked to it with something that has broken away. Being PVC it probably won't glue well, so it'd need a supporting pin and a major disassembly to get it replaced. Given I can still use mp3 cassettes in the deck I think I'm done.
On a whim I Googled the model number to see what was out there and found new parts for this and similar models.
It seems to be legit, I'm tempted to get a new cassette door and some other things.
https://www.encompassparts.com/model/HITTRK9150W/_/_/Hitachi/TRK9150W/