If you do decide to glue the gasket back in place, I wouldn't use silicone caulk. It's too hard to work with. A better choice would be Phenoseal, Polyseamseal or Lexel, all of which are water soluble until cured making clean-up of any excess much easier. I know that Lexel comes in clear, I'm not sure about the others.
With any of these products, I would consider it to be fairly permanent and hard to undo repair unless you use very, very little.
With any of these products, I would consider it to be fairly permanent and hard to undo repair unless you use very, very little.