UPDATE!
Will Woodgate from Stacks4Stacks has the perfect solution with his RandomImage stack: https://stacks4stacks.com/randomimage/
With this stack, you can randomly display warehoused images and set any value you wish to display as many images as you want. Amazingly, Will is offering this stack absolutely FREE! Plus it will work on as many domains as you like. I have donated 15 Euro in support of this stack as well as the many other great stacks that Stacks4Stacks have for free download.
If you want total control over when to display this, or any other stack, he has another suite of 5 stacks called AdvancedPublisher: https://stacks4stacks.com/advancedpublisher/ With this you can control all of the parameters for displaying content based on a plethora of time and date parameters. Download the free demo to try it out.
I want to give a shout-out to compliment Will on providing a great service to the Rapidweaver community. His many free stacks, and the very cool more advanced reasonable priced stacks he provides is amazing. PLus, his response to support questions are fast and comprehensive.
Well done, Will!