In short, not easily. It's a good question for someone getting started with the framework.
To see why, take a look at the exploit code here: https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/windows/smb/ms08_067_netapi.rb and see how functionality of the exploit is abstracted into disparate libraries.
Put another way, because MS08-067 is a remote SMB/DCERPC vulnerability, and the exploitation of that vulnerability requires interacting with a target via the SMB protocol, a standalone exploit would need to include, at a minimum: Ruby, the Ruby exploitation (rex) library, all network libraries necessary to trigger the bug, any error-handling code available in libraries, and the exploit / payload to be executed.
It's certainly possible to bundle just the necessary components of the framework to exploit a single vulnerability, but isn't the typical use case (and a somewhat more portable solution is to use the built-in libraries on windows - as standalone exploits often do), so most folks don't use the framework this way.