Occasionally someone loses something overboard and a futile search ensues. Now that I can roll I might consider goggles in calm water, but are there other options? I mean could something like a homebrew periscope work?
i’ll bite 
So, you find something under water. How do you get to it?
There is a “device” that you can make yourself. Take a plastic/metal can from coffee, cut bottom off, put plastic wrap on one end ( rubber band to hold it in place ).
If you stick the end with the wrap in the water you will be able to see things under water much better - reduced reflections from the rippling surface and shadow created by the walls helps quite a bit. At least used to ~20 years ago 
Yes
and it works fantastic.
Take a plastic five gallon bucket.
Cut a round hole in the bottom of it leaving about a inch or so around the edge.
Cut a circle of clear plexiglass that will lay on top of the rim that you left and glue it in place.
Hold the bucket a little way under the water surface, and you can see every thing as long as the water isn’t too cloudy.
It helps to put a hood over your head and the bucket to keep out the reflection from the sky.
Caution ! don’t get too carried away and lean too far over the side of your boat or dock and fall in.
Cheers,
JackL
Oh my…
That is High Tech stuff you are discussing
On the other hand, that 5gallon plastic bucket will have ~40 pounds of floatation, one could ~almost~ stand on it
aqua-vu
Or for a measly $599.99 you can go to cabelas and get yourself an underwater camera.
Try carrying a magnet
With 23 years of working around the water I have found that it seems to be knives, keys, and glasses that are most often lost. Carry a good strong magnet and some line and you should be able to fish out most things that are lost.
mask & roll
Or if the upside-down perspective is confusing, a mask and someone else’s bow is a fine way to look at the bottom without leaving your boat.