If you find SQL Reporting Services web parts missing from your MOSS SharePoint installation, try the following to fix.
This assumes you have SQL Server 2005 running on the same machine as MOSS 2007. If not, simply copy the RSWebParts.cab I show in the path below to your MOSS server.
Then get to a command prompt on the MOSS 2007 box and use the following:
stsadm.exe -o addwppack -filename "C:\Program Files\Microsoft SQL Server\90\Tools\Reporting Services\SharePoint\RSWebParts.cab"
where STSADM.EXE is a SharePoint utility, by default located in C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\BIN.