Originally Posted by Panama Red
I cut a piece of aluminum and replaced the plastic with that. Both of the plastic skylight vents were leaking on my 74 Sov. I really didn't see the need for the plastic anyways, so I just replaced it with aluminum...
If you have to have the plastic, any of the big box hardware stores sell plexi that you can cut to size.
I guess you didn't look at his picture, he doesn't have the aluminum lid with a plastic covered hole, he has an all plastic vent lid which can be purchased at any RV dealer.
Note those cheep plastic lids don't last that long.
I would just get a Fantastic Fan or Maxair to replace the whole thing (they use a higher quality plastic) or at least after replacing the cheep plastic lid get a vent cover to mount over it to protect it from the sun and as a bonus you can leave the vent open in bad weather with the Maxair or the cover.