I made a post in your WTB topic before I saw this topic. I will repeat what others have said: you can make your own keyboard cable in about an hour's time as long as you have: scissors, soldering iron, and a telephone handset cord.
You just cut the cord in two, then reverse the wire connections. You'll see they're colored, so just flip one side of the cut cord around and solder it back together. I'm going to write an entry on doing this in my Mac 512K blog pretty soon; I did it myself about 3 or 4 weeks ago.
Once you do this, the cord won't work on the telephone anymore. That's the only downside. ;-)
I do know if you plug in the cable that is wrongly pinned, it will FRY the keyboard.
Not true. Neither the Macintosh nor the keyboard will be harmed. Look at the pinout in Inside Macintosh.
I tried it out before I cut the telephone cord, and it will not harm the Macintosh or the keyboard. All that happens is that nothing happens. ;-)