This is a great idea! I would really like to help with this. I've signed up to volunteer at FOSS4G, but I'm unsure if I'll have funding from the University or any other sources to actually be able to go. If I do find I have the resources to attend, I'll let you know and would be more than happy to help staff and run this exhibition.
I'm exploring the possibility to exhibit PostgreSQL at FOSS4G in Calgary, Alberta, Canada, over August 24-29, 2020.
Part of this includes determining who is available to staff and run the exhibition. Please contact me directly if you are interested or know someone who might be able to help.