What kind of glue is best to replace lenses and dust gasket?

The glue holding the dust gasket around the eye cups came off and now there is a lot of dust on the screens. I am planning on getting a replacement gasket and taking out the lenses to clean the screens. Does the replacement gasket come with glue? If not what type of glue should I use to secure the gasket to the lenses and what type of glue to secure the lenses to the eye cups?