Is there a simple and reliable way that I can check the gps and get the newest up to date operating system/version in this model?
Firmware updates can be downloaded from this page (link)
The latest is Ver. 3.70 as of Jul 02, 2008. You can also use WebUpdater— "Garmin's free new application that automatically detects and installs the most recent version of operating software for your compatible Garmin GPS."(link)
What is the newest version for the 60SCx model of gps.
I don't think the hardware has changed much. Different region versions are listed here (link)