Win2k3 SP1 CD required

Forgive me in advance for something that may be obvious.

I initially installed the os from non-sp1 media and have since patched with windows updates to latest.

I am now adding windows components (bits) to my win 2k3 R2 server and being prompted for the SP1 cd. My original cd’s aren’t sp1 so how do I proceed to get the required files installed.

thanks