Thanks for all the suggestions and helpful hints.
I found what I was looking for when I started searching for "Keyhole Brackets".
This particular bracket is what is used on my daughters pop-up to hold a small gas stove onto the side of her trailer, for use outside.
She never uses the stove, so I thought I could find a couple of brackets and make her a small table to mount in the same location.
If I can find some proper materials for use as a tabletop, then I believe I can get something worked up for her.
Thanks again for all the help and ideas.
Jerry