I've searched for this application, but it doesn't appear to be available. I've also visited the official Samsung website, and there are downloads for this device regarding drivers, tools, etc., but nothing on the ScanMGR.
However, I recommend visiting Samsung Support to check for alternatives: http://www.samsung.com/us/support/owners/product/SCX-4623F/XAA
Note: Scroll down and expand the downloads to see all the available options.