Not all CETME rifles were created equal. Depending on who put together your rifle (especially if it is a Century Arms Intl), you may have to try different mounts to get one that fits properly and holds zero.
That said, the MFI mount that hk91 mentioned above is a very good option as you can adjust the fitment somewhat. Instead of the typical claw-lock mount, it provides a low profile picatinny rail interface which allows you to get a lower scope mount with standard rings. It mounts up with 4 screws to the standard mounting tabs. A little blue loctite on the threads to hold it fast and it should work well for you.
Just remember to keep the length of your scope short enough (with a small enough bell diameter) as to not interfere with the cocking lever locking back and your operation of the lever itself when charging the rifle. I see a lot of people putting ridiculously large scopes on these rifles and it is more than a little overkill and often hinders the shooter more than it helps.
