I just got back from a shoot at the beach, got some awesome sunset scenes, of course it was windy and the sound is crap, I forgot to turn the windscreen function on :(

In normal shooting I found the internal mics to be more than adequate and was wondering if there are any foam wind screens for the built in mics? I could just make my own of course, tape some foam over them? Is there a special kind of foam that works better?