Here's the latest from Adobe – it's now widely available and supported:
"You can download the Acrobat 64-bit installers from this page by clicking the appropriate download button below. After the download is complete, follow the installation steps below to begin the installation."
https://helpx.adobe.com/acrobat/kb/download-64-bit-installer.html
[Previously:
"Currently, Acrobat DC 64-bit for Windows is available in the following geographies - Australia, Brazil, France, Germany, India, Italy, Japan, New Zealand, and the UK. We plan to add more geographies in the coming months."]