It is a bit confusing but remember that it is the wide flat plastic IDE cable that is 80wire and 40 pin.
The IDE hard drive you want is just the standard 40 pin drive. So virtually any IDE hard drive will do.
Any of these 116 from dabs click here will work. The only limitation may be the size of drive your computer can accept.
Same with these from novatech click here
try and get a 7200 drive with either 8mb or 16mb cache. These are the best performers in IDE hard drives.