I don’t know of any product per say, but a sheet of plywood, a couple of two by fours and some L brackets and you’ll have what you need for about $40 US.
I asked this question a couple of years ago and never got a response. I looked through various
types of vendors and found nothing. I think the plywood and two by fours is a good solution. Using
the lightest weight materials you can find would make it more manageable, cheaper (maybe) and still serve the purpose.