macOS 10.12.6 available
How can download it from Mac Store?
10.12.6 is showing up on my App Store, sometimes it takes a bit of time to reach everyone.
Otherwise you can download the Combo from here,
https://support.apple.com/kb/DL1931?viewlocale=en_US&locale=en_US although you will not be able to install it right away you need to modify the distribution file and then repackage the download, its all a bit of a faff. Here are the instructions.
Modifying the Combo Updaters for Sierra.
Download Combo.
Open Combo.
Move Combo .pkg to desktop.
Open terminal.
Enter pkgutil —expand ~/Desktop/macOsUpdCombo10.12.6.pkg ~/Desktop/Expanded
Open Expanded folder and then open Distribution file in Text Wrangler
Change Distribution file, change Board iD line 21 to <your Macs boardID> at line 29 remove <your Mac model>
Save As .xml file to the Desktop
In Terminal chmod +x ~/Desktop/distribution.xml
Remove the extension .xml
Move new Distribution file to expanded package replacing the original
In terminal pkgutil —flatten ~/Desktop/Expanded ~/Desktop/Modified.pkg
Using the .pkg extension is crucial.
The Modified package on your desktop should now allow you to install the latest update
Please Note.
The dashes before the commands expand and flatten are two separate dashes but look like one long one here, please type the commands into terminal rather than copying and pasting as that will give an error.