Yes Possible.
Just plan the Disk space accordingly. for 5K i would suggest to use SQL instead of build in Embedded.
http://www.symantec.com/business/support/index?page=content&id=TECH96214
A single SEPM site should be sufficient for most environments with less than 25,000 machines
http://www.symantec.com/business/support/index?page=content&id=TECH92051&locale=en_US