If you desperately need the new Nexus 7, you could check out some other retail outlets like Best Buy, Walmart and of course, the Google Play Store. The latter started accepting orders for the two refreshed versions of the Google Nexus 7 with Google saying that orders will ship no later than July 30th.
Seeing Staples offer the new Nexus 7 before the July 30th launch date is not a surprise. Last year, a Kissimmee Staples started selling the 32GB version of the OG Google Nexus 7 more than a week before it was supposed to be on sale.
source: Amazon via AndroidCentral