How can I turn off receiving SMS (not iMessages) on os x mavericks?
SMS Handoff is not a feature on Mavericks, it needs Yosemite to function
[Thanks to @tubedogg for the confirmation]

To enable it you would start from your iPhone…
Settings > Messages > Text Message Forwarding - then add your computer from the list by switching on.

That will send a code to the computer, which you then enter on your phone to confirm the function - afaik, Mavericks will never receive that number, only Yosemite.

Switching off is
Settings > Messages > Text Message Forwarding again &amp; simply turn off forwarding that computer.