If you’re willing to get some quotes, it might be a good idea to grab Piccolo hardware, too.
Here’s the quote from McMaster Carr for 15 sets of hardware plus spares:
That’s USD and not including shipping. Fastenal (locally) was over double that price.
The gotcha here is that most of the hardware we need are low-profile socket heads and low-profile/jam nuts. They cost a fair amount more. I’ve already tried regular nuts, and they don’t fit into the Piccolo parts at all.