Half day rental

I'm in Denver and my partner is obsessed with the MX5. He's got a birthday coming up and while buying a Miata is a tad too soon, I'd like to make his birthday special by being able to drive one for a couple of hours. I've been reaching out to cat dealers and looking at rental places, but it seems impossible to fulfill that dream for him. Does anyone here have any ideas how I could pull that off?