About a year ago, I bought a used Yamaha AV-1 home theater system from
a coworker. The system has since been discontinued. A few months ago,
after moving, the system connector cable (which connects the receiver
with the subwoofer) was damaged. Basically, 2 of the 8 pins in the
connector were bent and broke off. This has rendered the system
unuseable.

So far, I have been unable to find a replacement cable at any large
retailer (Best Buy, Good Guys, Circuit City) and I just don't know
enough about this stuff to know if any of the cables that I have seen
online will work. Can I just order any 8-pin mini DIN cable and use
that?

The owner's manual doesn't list any replacement cables (in fact, it
basically says "Don't damage the cable or it won't work"). I have
tried contacting Yamaha via their web site and sent an email to their
service dept with no responses.

The connection is detailed in the owner's manual on page E-12:
http://www.yamaha.com/yec/customer/manuals/10AV-1EF.PDF

If you zoom in on that page, you can see the 8-pin layout like so:
     . . .
    .  . .
      . .

Where can I find a replacement cable?

Jackih-ga

This system is quite old and you are correct, it is in fact an 8-pin
DIN cable.
http://www.lastar.net/resources/din.asp

Any Mini 8-pin Male/Male DIN connector should do the trick for
connecting them.  The cable heads are exactly the same size and have
the same pin pattern.  I personally own such a cable and have measured
the sizes of it.

You can purchase these cables at any electronics store, or you can
visit one of the following links to purchase it online:
http://www.videocapturecard.com/8pincable12.html
http://www.lastar.net/product.asp?cat%5Fid=306&sku=28190
http://www.connectworld.net/cgi-bin/iec/M1521-25
http://www.cablestogo.com/product.asp?cat%5Fid=1303&sku=28191

I hope this fixes your problem.

-Tox-ga

Thanks, just the answer I was hoping for! I suspected that I could use
any 8-pin mini DIN, I will try it out this weekend.