Genarts Sapphire flicker remove is the thing to try on Sapphire
http://www.genarts.com/effects/sapphire#tabs-8
But as John says its sometimes tricky to totally remove this kind of thing.
I think the trial lasts 2 weeks so you can give it a shot. If you need any longer you can rent the FX too.
best wishes
Neil
http://www.patience.tv