if it's a g3 ibook i would rather consider getting a new ibook. The tray load combo drives are still in the 200 dollar range, and depending on what speed your g3 is that can already be a 1/3 of the total value of your ibook. Or find an external drive if you cant afford the grand for a new one. You didn't mention if your were a tech or not, you still have to consider the cost of installing the drive which could be another 100-200 in labor.
I was almost faced with the prospect of paying for a new drive for my ibook, but luckily apple covered it even tho i was 2 days beyond my applecare.