There is a Blackberry Repair Guide that shows how to open a Blackberry and replace the lens yourself. Once it is open it's as easy as taking the broken lens off the front assembly and installing a new one, the parts are available on ebay. There are also third party blackberry repair services that will do this for you. The lens is pretty much just glued into the front plate, take a plastic prying tool to avoid scratches and pry the broken lens off.

Hi.....don't know if you have already resolved this problem, but if not, you can view this video on you tube which shows you exactly how to do it. This doesn't say 8330 but still applies same as the others.  BlackBerry 8300 8310 8320 lens replacement proceedure

Use a hair dryer to warm up the lens and soften the adhesive. Carefully pry it off the case. Remove the contact paper and protective film on the new lens and place it on the case. Clean all traces of finger prints from the back side of the lens before putting it back together!