Is it okay to set them out? Yes, definitely.
Is it okay for you to have them printed? If you insist… but Stack Exchange is happy to do it.
If there's enough time (this weekend?), you can email a PDF to me at dori (at) stackexchange, and I can have the amazing Amanda find a printer near you where you can pick them up.
We're always happy to see people promoting their sites, and want to make it as easy as possible for you to do so.
For anyone reading this in the future: want some help with site promotion? Just let us know what we can do (and thanks)!
Followup:
Amanda worked with the printer @ændrük recommended, and he'll be able to pick them up this afternoon (you see why I said she was amazing?).
ændrük, let us know in enough time, and we'll see about helping to sponsor the conference next year. But most importantly, thanks so much for helping to make this happen.
I love it when a plan comes together!