Here is also a link to a tutorial from a company who sell individual keys , i order many times from them:)
http://www.youtube.com/profile?user=laptopkeycom#p/u/39/iHHcOxTRXng

Hello, the best you can do is get a replacement key, I too had a broken hinge under the ENTER key and recently got a new key kit from http://www.laptopkey.com , they sell individual keys at a very reasonable price and they service is great ... I got by keys in just 3 days