Microsoft has been making a lot of changes to the list of VMs available in each region.
I recently took an online class and the instructor wanted us to choose one of the cheaper tiers but the one he suggested wasn't available anymore.
This is a neat site you can use to find the available VMs per region:
VM Model Search Tool
You can start by typing 'virtual machines' into the search box and it will show you all of the different models available per region.