I bought my first portable - a Sony TPS-L2 - when I was 16 years old. I had to sell a lot of my comic book collection to buy it, but it was well worth it. Of course, now I wish I would have kept the comics and the Walkman! I recently purchased a mint Sony Walkman Professional WM-D3 from a seller on Offer Up for $10. The thing is immaculate, right down to its perfect original carry case and strap. After cleaning and demagnetizing the heads the machine played perfectly for about 5 minutes, then stopped. All you hear now when engaging the transport buttons is the click-clack of the gears. Surely, the center gear has cracked. I did quite a bit of research before coming across the post on stereo2go.com that talks about a replacement gear being created. Very much interested in further developments.
Welcome Orlando! Nice story! I see you already found the correct thread for your cracked gear! For the price you paid for the D3, i think you can allow yourself a new gear for iT!