So I was getting my Japanese practice in for the day by searching for Japanese websites to see what solutions they have for replacing broken gears on PCE CD-ROMs. And what I found was kind of surprising.
First, there's a guy on Yahoo Japan Auctions who sells exact replacement gears, seemingly on a regular basis. It looks like he just sells one at a time, with the auctions starting at (and usually ending at) Y1100 (about $11)
Here's the current one
http://page18.auctions.yahoo.co.jp/jp/auction/w100388482The seller is yaohati33
The other solution I found was two separate pages that shows how to combine two component gears to make a replacement compound gear
http://garakuta.homelinux.org/~nosuke/diary/diary.html?y=2009&m=6&d=3&n=1This first one gives a source for the gears, kkpmo.com. He spent about $41 on the parts to make 5 gears. He drilled out the inside diameter and glued them together with what seems to be some specialized glue.
http://pcerepair.blog.fc2.com/blog-category-1.htmlThis guy had the same idea, but he went about it a couple different ways. (and this one I didn't try to read much, I just skimmed it.
First, he tried binding them with heat (and a takoyaki cooker?!)
Then he pinned them together with piano wire (looks effective, but difficult)
Then he found the same glue the guy in the first page did.
In later posts, he goes on to show some custom gear setups, including an alternate 3 gear arrangement and a belt drive system. The latter of which he says came from a foreigner. Someone here, perhaps?