I've been doing some searcing lately for knobs myself. I've seen ones that looked just like that at Radio Shack and HomeDepot. Can't really give you a name, but if you browse around you'll find em'.
The dark gray foam ring around the eye is backer-rod, it's meant to stuff into deep crevices around windows before you caulk, rather than filling the gap entirely with caulk.
I also know what the peice of wavy sheetmetal is behind the lenses, but I can't place it right now, it's driving me crazy.
I think the lense frames come from a better-quality jewelers loup.