Google Play ran out of inventory of their WiFi models of the Nexus 7 in both 16GB and 32GB configurations earlier this month, but you were able to still order the Nexus 7 LTE, which included a free shipping offer. It looks like the free shipping offer worked because they too are now out of stock.
The three models of the Nexus 7, 16GB/32GB Wifi and LTE as well as the Nexus 10, in both 16GB and 32GB configs are all out of stock. This leaves no Nexus tablets available to purchase from Google Play. What does this mean? Well, the Nexus 7 will be 12 months old on the 26th of July, which is when it went on sale in the US last year. It could be replaced by a Nexus 7(2014) in the next few months, or Google may decide to simply move onto the Nexus 9, which leaked on Sunday.
There still seems to be stock of the Nexus 7 at retailers in Australia, although most retailers seem to only have the 32GB WiFi and LTE versions. The 16GB Nexus 7 is apparently scarce though with retailers JB HiFi, The Good Guys and Dick Smith showing only a 32GB Model(GoodGuys still has the LTE version) available, so perhaps retail stock is dwindling now as well.
Do you want a Nexus 7, or are you going to hold off until the Nexus 9?