Roger CETME came in 1957 with input from German engineers and HK. It is based on the German StG45 delayed roller block system and originally fired the same round as the StG45 but with input from HK the caliber was changed to 7.62 x 51. Either way they are good guns.
Buckeye depending on where you are at there may be some G3's or FN's floating around that you may be able to handle and shoot.
You cannot go wrong with a DSA gun they are great shooters. Also check Arizona Response Systems they make FN's also.
Good luck, stay safe and Semper Fi.