re-load SQL Server Desktop engine for sharpoint services 2.0

client deleted SQL server desktop for sharepoint, trying to free up space on C ????
And of course now their company web doesn’t work. Can the SQL be loaded standalone? Can the SBS 2003 disks repair this, without reloading system settings for everything else?
And can the calendar be uploaded from the outlook one that used to reference the vacation planner in Sharepoint?
using:
Microsoft SBS 2003
Sharepoint services 2.0

Thanks much
–C