You must be wondering around looking for SCEP Offline Installers. Since the installers, can be acquired only from WSUS.
Good news, I have found Microsoft Office link on downloading SCEP Offline Installers.
Here is some of the official offline installer where you can download directly without WSUS.
1.SCEP Version 4.10.209.0
2.SCEP Version 4.7.209.0